Author: "Philippe, Moisy" / Language: english - Searchworks@Jio Institute Digital Library Search Results

Your search keyword '"Philippe, Moisy"' showing total 78 results

Start Over Author "Philippe, Moisy" Language english

78 results on '"Philippe, Moisy"'

1. X-ray absorption spectroscopy and actinide electrochemistry: a setup dedicated to radioactive samples applied to neptunium chemistry

Author: Richard Husar, Thomas Dumas, Michel L. Schlegel, Daniel Schlegel, Dominique Guillaumont, Pier-Lorenzo Solari, and Philippe Moisy
Subjects: x-ray absorption spectroscopy, xas, actinide, electrochemistry, radioactive sample, neptunium chemistry, Nuclear and particle physics. Atomic energy. Radioactivity, QC770-798, Crystallography, QD901-999
Abstract: A spectroelectrochemical setup has been developed to investigate radioactive elements in small volumes (0.7 to 2 ml) under oxidation–reduction (redox) controlled conditions by X-ray absorption spectroscopy (XAS). The cell design is presented together with in situ XAS measurements performed during neptunium redox reactions. Cycling experiments on the NpO22+/NpO2+ redox couple were applied to qualify the cell electrodynamics using XANES measurements and its ability to probe modifications in the neptunyl hydration shell in a 1 mol l−1 HNO3 solution. The XAS results are in agreement with previous structural studies and the NpO22+/NpO2+ standard potential, determined using Nernst methods, is consistent with measurements based on other techniques. Subsequently, the NpO2+, NpO22+ and Np4+ ion structures in solution were stabilized and measured using EXAFS. The resulting fit parameters are again compared with other results from the literature and with theoretical models in order to evaluate how this spectroelectrochemistry experiment succeeds or fails to stabilize the oxidation states of actinides. The experiment succeeded in: (i) implementing a robust and safe XAS device to investigate unstable radioactive species, (ii) evaluate in a reproducible manner the NpO22+/NpO2+ standard potential under dilute conditions and (iii) clarify mechanistic aspects of the actinyl hydration sphere in solution. In contrast, a detailed comparison of EXAFS fit parameters shows that this method is less appropriate than the majority of the previously reported chemical methods for the stabilization of the Np4+ ion.
Published: 2022
Full Text: View/download PDF

2. Investigation of the Plutonium(IV) Interactions with Two Variants of the EF-Hand Ca-Binding Site I of Calmodulin

Author: Loïc Daronnat, Vanessa Holfeltz, Nathalie Boubals, Thomas Dumas, Philippe Guilbaud, Diego Moreno Martinez, Philippe Moisy, Sandrine Sauge-Merle, David Lemaire, Pier Lorenzo Solari, Laurence Berthon, Catherine Berthomieu, Interactions Protéine Métal (IPM), Institut de Biosciences et Biotechnologies d'Aix-Marseille (ex-IBEB) (BIAM), Aix Marseille Université (AMU)-Centre National de la Recherche Scientifique (CNRS)-Direction de Recherche Fondamentale (CEA) (DRF (CEA)), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Aix Marseille Université (AMU)-Centre National de la Recherche Scientifique (CNRS)-Direction de Recherche Fondamentale (CEA) (DRF (CEA)), and Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)
Subjects: Inorganic Chemistry, [SDV]Life Sciences [q-bio], Physical and Theoretical Chemistry
Abstract: International audience; Due to its presence in the nuclear industry and its strong radiotoxicity, plutonium is an actinide of major interest in the event of internal contamination. To improve the understanding of its mechanisms of transport and accumulation in the body, the complexation of Pu(IV) to the most common protein calcium-binding motif found in cells, the EF-hand motif of calmodulin, was investigated. Visible and X-ray absorption spectroscopies (XAS) in solution made it possible to investigate the speciation of plutonium at physiological pH (pH 7.4) and pH 6 in two variants of the calmodulin Ca-binding site I and using Pu(IV) in different media: carbonate, chloride, or nitrate solutions. Three different species of Pu were identified in the samples, with formation of 1:1 Pu(IV):calmodulin peptide complexes, Pu(IV) reduction, and formation of peptide-mediated Pu(IV) hexanuclear cluster.
Published: 2023
Full Text: View/download PDF

3. First observation of [Pu6(OH)4O4 ]12+ cluster during the hydrolytic formation of PuO2 nanoparticles using H/D kinetic isotope effect

Author: Manon Cot-Auriol, Matthieu Virot, Thomas Dumas, Olivier Diat, Denis Menut, Philippe Moisy, Sergey I. Nikitenko, Sonochimie dans les Fluides Complexes (LSFC), Institut de Chimie Séparative de Marcoule (ICSM - UMR 5257), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS)-Université de Montpellier (UM)-Ecole Nationale Supérieure de Chimie de Montpellier (ENSCM), Université de Montpellier (UM)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS)-Université de Montpellier (UM)-Ecole Nationale Supérieure de Chimie de Montpellier (ENSCM), Université de Montpellier (UM), Institut des Sciences et technologies pour une Economie Circulaire des énergies bas carbone (ISEC), CEA-Direction des Energies (ex-Direction de l'Energie Nucléaire) (CEA-DES (ex-DEN)), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA), Ions aux Interfaces Actives (L2IA), Synchrotron SOLEIL (SSOLEIL), and Centre National de la Recherche Scientifique (CNRS)
Subjects: Materials Chemistry, Metals and Alloys, Ceramics and Composites, General Chemistry, [CHIM.INOR]Chemical Sciences/Inorganic chemistry, [CHIM.RADIO]Chemical Sciences/Radiochemistry, Catalysis, Surfaces, Coatings and Films, Electronic, Optical and Magnetic Materials
Abstract: New insights are provided about the formation mechanism of PuO2 nanoparticles (NPs) by investigating an unprecedented kinetic isotope effect observed during their hydrolytic synthesis in H2O or D2O media.
Published: 2022
Full Text: View/download PDF

4. Synthesis and multi-scale properties of PuO2 nanoparticles: recent advances and open questions

Author: Matthieu Virot, Thomas Dumas, Manon Cot-Auriol, Philippe Moisy, Sergey I. Nikitenko, Sonochimie dans les Fluides Complexes (LSFC), Institut de Chimie Séparative de Marcoule (ICSM - UMR 5257), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS)-Université de Montpellier (UM)-Ecole Nationale Supérieure de Chimie de Montpellier (ENSCM), Université de Montpellier (UM)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS)-Université de Montpellier (UM)-Ecole Nationale Supérieure de Chimie de Montpellier (ENSCM), Université de Montpellier (UM), Institut des Sciences et technologies pour une Economie Circulaire des énergies bas carbone (ISEC), CEA-Direction des Energies (ex-Direction de l'Energie Nucléaire) (CEA-DES (ex-DEN)), and Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)
Subjects: General Engineering, General Materials Science, Bioengineering, General Chemistry, [CHIM.INOR]Chemical Sciences/Inorganic chemistry, [CHIM.RADIO]Chemical Sciences/Radiochemistry, Atomic and Molecular Physics, and Optics
Abstract: The review focuses on the recent relevant progresses observed about PuO2 nanoparticle syntheses and characterizations including the recently deciphered electronic, structural and physico-chemical properties.
Published: 2022
Full Text: View/download PDF

5. Sonochemistry of actinides: from ions to nanoparticles and beyond

Author: Sergey I. Nikitenko, Matthieu Virot, Philippe Moisy, Sonochimie dans les Fluides Complexes (LSFC), Institut de Chimie Séparative de Marcoule (ICSM - UMR 5257), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS)-Université de Montpellier (UM)-Ecole Nationale Supérieure de Chimie de Montpellier (ENSCM), Université de Montpellier (UM)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS)-Université de Montpellier (UM)-Ecole Nationale Supérieure de Chimie de Montpellier (ENSCM), Université de Montpellier (UM), Institut des Sciences et technologies pour une Economie Circulaire des énergies bas carbone (ISEC), CEA-Direction des Energies (ex-Direction de l'Energie Nucléaire) (CEA-DES (ex-DEN)), and Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)
Subjects: [CHIM]Chemical Sciences, Physical and Theoretical Chemistry, [CHIM.RADIO]Chemical Sciences/Radiochemistry
Abstract: Sonochemistry studies chemical and physical effects in liquids submitted to power ultrasound. These effects arise not from a direct interaction of molecules with sound waves, but rather from the acoustic cavitation: the nucleation, growth, and implosive collapse of microbubbles in liquids submitted to power ultrasound. The violent implosion of bubbles leads to the formation of chemically reactive species. In principle, each cavitation bubble can be considered as a microreactor initiating chemical reactions at mild conditions. In addition, microjets and shock waves accompanied bubble collapse produce fragmentation, dispersion and erosion of solid surfaces or particles. Microbubbles oscillating in liquids also enable nucleation and precipitation of nanosized actinide compounds with specific morphology. This review focuses on the versatile sonochemical processes with actinide ions and particles in homogenous solutions and heterogenous systems. The redox reactions in aqueous solutions, dissolution or precipitation of refractory solids, synthesis of actinide nanoparticles, and ultrasonically driving decontamination are considered. The guideline for further research is also discussed.
Published: 2022
Full Text: View/download PDF

6. Dipolar and contact paramagnetic NMR chemical shifts in An$^{IV}$ complexes with dipicolinic acid derivatives

Author: Md. Ashraful Islam, Matthieu Autillo, Laetitia Guérin, Christelle Tamain, Philippe Moisy, Hélène Bolvin, Claude Berthon, International Rice Research Institute [Philippines] (IRRI), Consultative Group on International Agricultural Research [CGIAR] (CGIAR), International Rice Research Institute IRRI, Systèmes étendus et magnétisme (LCPQ) (SEM), Laboratoire de Chimie et Physique Quantiques Laboratoire (LCPQ), Université Toulouse III - Paul Sabatier (UT3), Université de Toulouse (UT)-Université de Toulouse (UT)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS)-Fédération de recherche « Matière et interactions » (FeRMI), Institut National des Sciences Appliquées - Toulouse (INSA Toulouse), Institut National des Sciences Appliquées (INSA)-Université de Toulouse (UT)-Institut National des Sciences Appliquées (INSA)-Université de Toulouse (UT)-Université Toulouse III - Paul Sabatier (UT3), Université de Toulouse (UT)-Centre National de la Recherche Scientifique (CNRS)-Institut National des Sciences Appliquées - Toulouse (INSA Toulouse), Institut National des Sciences Appliquées (INSA)-Université de Toulouse (UT)-Institut National des Sciences Appliquées (INSA)-Centre National de la Recherche Scientifique (CNRS)-Université Toulouse III - Paul Sabatier (UT3), Institut National des Sciences Appliquées (INSA)-Université de Toulouse (UT)-Institut National des Sciences Appliquées (INSA)-Centre National de la Recherche Scientifique (CNRS), Commission des méthodes d'analyse du CEA (CETAMA), Département de recherche sur les procédés pour la mine et le recyclage du combustible (DMRC), CEA-Direction des Energies (ex-Direction de l'Energie Nucléaire) (CEA-DES (ex-DEN)), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-CEA-Direction des Energies (ex-Direction de l'Energie Nucléaire) (CEA-DES (ex-DEN)), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA), Laboratory of Interactions Ligand-Actinide (LILA), and ANR-17-CE06-0010,ACTIpNMR,déplacements de RMN paramagnétiques pour les actinides : au délà du modèle des lanthanides(2017)
Subjects: Inorganic Chemistry, Bleaney's theory, ab initio calculations, paramagnetic NMR spectroscopy, covalency, [CHIM.COOR]Chemical Sciences/Coordination chemistry, Physical and Theoretical Chemistry, Actinide
Abstract: International audience
Published: 2022
Full Text: View/download PDF

7. Ultrasonically assisted conversion of uranium trioxide into uranium( vi ) intrinsic colloids

Author: Christophe Den Auwer, Xavier Le Goff, Olivier Diat, Thomas Dumas, Cyril Micheau, Manon Cot-Auriol, Philippe Moisy, Matthieu Virot, Sergey I. Nikitenko, Sonochimie dans les Fluides Complexes (LSFC), Institut de Chimie Séparative de Marcoule (ICSM - UMR 5257), Centre National de la Recherche Scientifique (CNRS)-Institut de Chimie du CNRS (INC)-Université de Montpellier (UM)-Ecole Nationale Supérieure de Chimie de Montpellier (ENSCM)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Centre National de la Recherche Scientifique (CNRS)-Institut de Chimie du CNRS (INC)-Université de Montpellier (UM)-Ecole Nationale Supérieure de Chimie de Montpellier (ENSCM)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA), Département de recherche sur les procédés pour la mine et le recyclage du combustible (DMRC), CEA-Direction des Energies (ex-Direction de l'Energie Nucléaire) (CEA-DES (ex-DEN)), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA), Etude de la Matière en Mode Environnemental (L2ME), Institut de Chimie de Nice (ICN), Université Nice Sophia Antipolis (... - 2019) (UNS), COMUE Université Côte d'Azur (2015-2019) (COMUE UCA)-COMUE Université Côte d'Azur (2015-2019) (COMUE UCA)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS)-Université Côte d'Azur (UCA), Ions aux Interfaces Actives (L2IA), Commission des méthodes d'analyse du CEA (CETAMA), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-CEA-Direction des Energies (ex-Direction de l'Energie Nucléaire) (CEA-DES (ex-DEN)), Centre National de la Recherche Scientifique (CNRS)-Institut de Chimie du CNRS (INC)-Université de Montpellier (UM)-Ecole Nationale Supérieure de Chimie de Montpellier (ENSCM)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Ecole Nationale Supérieure de Chimie de Montpellier (ENSCM)-Institut de Chimie du CNRS (INC)-Université de Montpellier (UM)-Centre National de la Recherche Scientifique (CNRS)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Ecole Nationale Supérieure de Chimie de Montpellier (ENSCM)-Institut de Chimie du CNRS (INC)-Université de Montpellier (UM)-Centre National de la Recherche Scientifique (CNRS), Université Nice Sophia Antipolis (1965 - 2019) (UNS), and Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Ecole Nationale Supérieure de Chimie de Montpellier (ENSCM)-Institut de Chimie du CNRS (INC)-Université de Montpellier (UM)-Centre National de la Recherche Scientifique (CNRS)
Subjects: Chemistry, Inorganic chemistry, chemistry.chemical_element, Nanoparticle, 02 engineering and technology, Uranium, 010402 general chemistry, 021001 nanoscience & nanotechnology, Uranyl, complex mixtures, 01 natural sciences, 0104 chemical sciences, Inorganic Chemistry, chemistry.chemical_compound, 13. Climate action, Uranium trioxide, Oxidizing agent, [CHIM]Chemical Sciences, Reactivity (chemistry), Leaching (metallurgy), 0210 nano-technology, Schoepite
Abstract: Under oxidizing conditions, the corrosion of spent nuclear fuel may lead to the leaching of radionuclides including soluble uranyl-based species. The speciation of the generated chemical forms is complex and the related potential formation of colloidal species appears surprisingly poorly reported in the literature. Their formation could however contribute significantly to the mobility of radionuclides in the environment. A better knowledge in the speciation and reactivity of these species appears particularly relevant. This study describes the preparation and characterization of intrinsic uranium(VI) colloids from amorphous and crystalline UO3 in pure water assisted by 20 kHz ultrasound. In the presence of carbon monoxide preventing the sonochemical formation of hydrogen peroxide, ultrasonic treatment boosts the conversion of UO3 powder into (meta-)schoepite precipitates and yields very stable and notably concentrated uranium(VI) nanoparticles in the liquid phase. Using HR-TEM, SAXS and XAS techniques, we confirmed that the colloidal suspension is composed of quasi-spherical nanoparticles measuring ca. 3.8 ± 0.3 nm and exhibiting a schoepite-like crystallographic structure. The proposed method demonstrates the possible formation of environmentally relevant U(VI) colloidal nanoparticles appearing particularly interesting for the preparation of reference systems in the absence of added ions and capping agents.
Published: 2021
Full Text: View/download PDF

8. Electrochemical Behavior of Ce(IV)/Ce(III) Couple in N,N‐Di(2‐ethylhexyl)‐n‐butanamide (DEHBA), N,N‐Di(2‐ethylhexyl)‐iso‐butanamide (DEHiBA), and N,N‐Di(2‐ethylhexyl)‐3,3‐dimethyl Butanamide (DEHDMBA)

Author: Fethi Bedioui, Philippe Moisy, Amivi Felicite Amoudji, Sylvie Arpigny, Commission des méthodes d'analyse du CEA (CETAMA), Département de recherche sur les procédés pour la mine et le recyclage du combustible (DMRC), CEA-Direction des Energies (ex-Direction de l'Energie Nucléaire) (CEA-DES (ex-DEN)), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-CEA-Direction des Energies (ex-Direction de l'Energie Nucléaire) (CEA-DES (ex-DEN)), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA), Ecole Nationale Supérieure de Chimie de Paris - Chimie ParisTech-PSL (ENSCP), and Université Paris sciences et lettres (PSL)
Subjects: dialkylamide, chemistry.chemical_element, PUREX, 010402 general chemistry, 010403 inorganic & nuclear chemistry, Electrochemistry, 01 natural sciences, cyclic voltammetry, 0104 chemical sciences, Analytical Chemistry, Cerium, cerium, chemistry, [CHIM.ANAL]Chemical Sciences/Analytical chemistry, [CHIM]Chemical Sciences, Cyclic voltammetry, Nuclear chemistry
Abstract: International audience; In this work we report on the electrochemical behavior of Ce(IV)/Ce(III) redox couple in pure N,N-dialkyl amides (N,N-DA), namely N,N-di(2-ethylhexyl)-n-butanamide (DEHBA), N,N-di(2-ethylhexyl)-iso-butanamide (DEHiBA), and N,Ndi(2-ethylhexyl)-3,3-dimethyl butanamide (DEHDMBA) equilibrated with nitric aqueous solutions as an entry to the direct electrochemical characterization of plutonium in these extractants. Ce(IV)/Ce(III) redox process was used as a model. Its potential (E 1/2  1.02 V/SCE) is not affected by the temperature and the nature of the N,N-DA and this clearly indicates that the functionalities of the these extractants produce the same relative effect on both +IV and +III oxidation states of the cerium cation. Linear variations of the current intensity of the reduction peak of Ce(IV) with the concentration of Ce(IV)/N,N-DAs/HNO 3 (5M) solutions were obtained from cyclic voltammograms recorded at 25°C and 40°C. Due to the poor definition of the voltammograms in DEHiBA and DEHDMBA, such characterization allows only the evaluation of the performances of the chemical extraction of Ce(IV) from aqueous nitric acid solution by the undiluted DEHBA. To our knowledge, the electrochemical behavior of Ce(IV)/Ce(III) in N,N-DAs was not previously studied and our findings will for sure open the door for further investigations in this field.
Published: 2021
Full Text: View/download PDF

9. Monitoring and Management of Anions in Polluted Aqua Systems: case studies on nitrate, chromate, pertechnetate and diclofenac

Author: Peter Hesemann, Philippe Moisy, Amitabh Banerji, Rana Ahmed, Andreas Taubert, Universität Potsdam, Commissariat à l'Energie Atomique, Centre de Marcoule (CEA), Institut Charles Gerhardt Montpellier - Institut de Chimie Moléculaire et des Matériaux de Montpellier (ICGM ICMMM), Ecole Nationale Supérieure de Chimie de Montpellier (ENSCM)-Centre National de la Recherche Scientifique (CNRS)-Université de Montpellier (UM)-Université Montpellier 1 (UM1)-Université Montpellier 2 - Sciences et Techniques (UM2)-Institut de Chimie du CNRS (INC), N.a. Oladoja, E.I. Unuabonah, University of Potsdam = Universität Potsdam, Institut Charles Gerhardt Montpellier - Institut de Chimie Moléculaire et des Matériaux de Montpellier (ICGM), and Ecole Nationale Supérieure de Chimie de Montpellier (ENSCM)-Institut de Chimie du CNRS (INC)-Université de Montpellier (UM)-Centre National de la Recherche Scientifique (CNRS)
Subjects: Pertechnetate, Environmental remediation, 02 engineering and technology, 010501 environmental sciences, 01 natural sciences, chemistry.chemical_compound, Diclofenac, Nitrate, Nuclear industry, medicine, ComputingMilieux_MISCELLANEOUS, 0105 earth and related environmental sciences, Pollutant, Chromate conversion coating, biology, [CHIM.MATE]Chemical Sciences/Material chemistry, 021001 nanoscience & nanotechnology, 6. Clean water, chemistry, 13. Climate action, Environmental chemistry, [SDE]Environmental Sciences, biology.protein, Environmental science, 0210 nano-technology, Organic anion, medicine.drug
Abstract: Anionic pollutants are widespread and pose severe environmental risks. This chapter focuses on four different anions as representative examples for various classes of anionic pollutants originating from various anthropogenic sources and activities: nitrate from agriculture, chromate from leather and tanning industries, pertechnetate from nuclear industry and military activities and finally, as an example of an organic anion, diclofenac from the pharmaceutical industry. All four anions pose different risks, but their management calls for similar remediation strategies. This chapter summarizes these strategies and discusses their challenges, their advantages and disadvantages.
Published: 2021

10. Real-Time Observation of Solvation Dynamics of Electron in Actinide Extraction Binary Solutions of Water and n-Tributyl Phosphate

Author: Jun Ma, Teseer Bahry, Mehran Mostafavi, Sergey A. Denisov, Philippe Moisy, Institut de Chimie Physique (ICP), Institut de Chimie du CNRS (INC)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS), Commission des méthodes d'analyse du CEA (CETAMA), Département de recherche sur les procédés pour la mine et le recyclage du combustible (DMRC), CEA-Direction des Energies (ex-Direction de l'Energie Nucléaire) (CEA-DES (ex-DEN)), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-CEA-Direction des Energies (ex-Direction de l'Energie Nucléaire) (CEA-DES (ex-DEN)), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA), and Nanjing University of Aeronautics and Astronautics [Nanjing] (NUAA)
Subjects: 010304 chemical physics, Absorption spectroscopy, Chemistry, Solvation, Electron, 010402 general chemistry, Mole fraction, 01 natural sciences, 0104 chemical sciences, Surfaces, Coatings and Films, Solvent, [CHIM.THEO]Chemical Sciences/Theoretical and/or physical chemistry, chemistry.chemical_compound, Chemical physics, 0103 physical sciences, Materials Chemistry, Water environment, Molecule, Tributyl phosphate, Physical and Theoretical Chemistry, ComputingMilieux_MISCELLANEOUS
Abstract: The excess electron in solution is a highly reactive radical involved in various radiation-induced reactions. Its solvation state critically determines the subsequent pathway and rate of transfer. For instance, water plays a dominating role in the electron-induced dealkylation of n-tributyl phosphate in actinide extraction processing. However, the underlying electron solvation processes in such systems are lacking. Herein, we directly observed the solvation dynamics of electrons in H-bonded water and n-tributyl phosphate (TBP) binary solutions with a mole fraction of water (Xw) varying from 0.05 to 0.51 under ambient conditions. Following the evolution of the absorption spectrum of trapped electrons (not fully solvated) with picosecond resolution, we show that electrons statistically distributed would undergo preferential solvation within water molecules extracted in TBP. We determine the time scale of excess electron full solvation from the deconvoluted transient absorption-kinetical data. The process of solvent reorganization accelerates by increasing the water molar fraction, and the rate of this process is 2 orders of magnitude slower compared to bulk water. We assigned the solvation process to hydrogen network reorientation induced by a negative charge of the excess electron that strongly depends on the local water environment. Our findings suggest that water significantly stabilizes the electron in a deeper potential than the pure TBP case. In its new state, the electron is likely to inhibit the dealkylation of extractants in actinide separation.
Published: 2021
Full Text: View/download PDF

11. Sonochemical dissolution of nanoscale ThO2 and partial conversion into a thorium peroxo sulfate

Author: Laura Bonato, Matthieu Virot, Xavier Le Goff, Philippe Moisy, Sergey I. Nikitenko, Sonochimie dans les Fluides Complexes (LSFC), Institut de Chimie Séparative de Marcoule (ICSM - UMR 5257), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Ecole Nationale Supérieure de Chimie de Montpellier (ENSCM)-Institut de Chimie du CNRS (INC)-Université de Montpellier (UM)-Centre National de la Recherche Scientifique (CNRS)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Ecole Nationale Supérieure de Chimie de Montpellier (ENSCM)-Institut de Chimie du CNRS (INC)-Université de Montpellier (UM)-Centre National de la Recherche Scientifique (CNRS), Etude de la Matière en Mode Environnemental (L2ME), CEA-Direction des Energies (ex-Direction de l'Energie Nucléaire) (CEA-DES (ex-DEN)), Commissariat à l'énergie atomique et aux énergies alternatives (CEA), Centre National de la Recherche Scientifique (CNRS)-Institut de Chimie du CNRS (INC)-Université de Montpellier (UM)-Ecole Nationale Supérieure de Chimie de Montpellier (ENSCM)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Centre National de la Recherche Scientifique (CNRS)-Institut de Chimie du CNRS (INC)-Université de Montpellier (UM)-Ecole Nationale Supérieure de Chimie de Montpellier (ENSCM)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Ecole Nationale Supérieure de Chimie de Montpellier (ENSCM)-Université de Montpellier (UM)-Centre National de la Recherche Scientifique (CNRS)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Ecole Nationale Supérieure de Chimie de Montpellier (ENSCM)-Université de Montpellier (UM)-Centre National de la Recherche Scientifique (CNRS), Département de recherche sur les procédés pour la mine et le recyclage du combustible (DMRC), and Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)
Subjects: Acoustics and Ultrasonics, Organic Chemistry, Inorganic chemistry, Thorium, chemistry.chemical_element, Sulfuric acid, 02 engineering and technology, [CHIM.INOR]Chemical Sciences/Inorganic chemistry, 010402 general chemistry, 021001 nanoscience & nanotechnology, 01 natural sciences, 0104 chemical sciences, Inorganic Chemistry, chemistry.chemical_compound, chemistry, Cavitation, Chemical Engineering (miscellaneous), Environmental Chemistry, [CHIM]Chemical Sciences, Radiology, Nuclear Medicine and imaging, Sulfate, 0210 nano-technology, Dissolution, Nanoscopic scale
Abstract: International audience; The influence of the sample morphology and experimental conditions towards the sonochemical dissolution of nanoscale ThO 2 samples in sulfuric acid media is described. Significant sonochemical dissolution rates and yields are observed at 20 kHz under Ar/O 2 atmosphere in dilute 0.5 M H 2 SO 4 at room temperature, contrasting with the generally-reported high refractory behavior for ThO 2. The dissolution of ThO 2 combines the physical effects driven by acoustic cavitation phenomenon, the complexing affinity of Th(IV) in sulfuric medium and the sonochemical generation of H 2 O 2. These sonochemical conditions further allow the observation of the partial conversion of ThO 2 into a scarce Th(IV) peroxo sulfate with 1D morphology resulting from one or both following processes: dissolution/ reprecipitation or formation of an intermediate Th(IV) surface complex.
Published: 2020
Full Text: View/download PDF

12. In situ study of the synthesis of thorite (ThSiO 4 ) under environmental representative conditions

Author: Jérémy Causse, Nicolas Dacheux, Adel Mesbah, Eleonore Welcomme, Paul Estevenon, Philippe Moisy, Christophe Poinssot, Stéphanie Szenknect, Interfaces de Matériaux en Evolution (LIME), Institut de Chimie Séparative de Marcoule (ICSM - UMR 5257), Centre National de la Recherche Scientifique (CNRS)-Institut de Chimie du CNRS (INC)-Université de Montpellier (UM)-Ecole Nationale Supérieure de Chimie de Montpellier (ENSCM)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Centre National de la Recherche Scientifique (CNRS)-Institut de Chimie du CNRS (INC)-Université de Montpellier (UM)-Ecole Nationale Supérieure de Chimie de Montpellier (ENSCM)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA), Département de recherche sur les procédés pour la mine et le recyclage du combustible (DMRC), CEA-Direction des Energies (ex-Direction de l'Energie Nucléaire) (CEA-DES (ex-DEN)), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA), Nanomatériaux pour l'Energie et le Recyclage (LNER), and Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Ecole Nationale Supérieure de Chimie de Montpellier (ENSCM)-Institut de Chimie du CNRS (INC)-Université de Montpellier (UM)-Centre National de la Recherche Scientifique (CNRS)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Ecole Nationale Supérieure de Chimie de Montpellier (ENSCM)-Institut de Chimie du CNRS (INC)-Université de Montpellier (UM)-Centre National de la Recherche Scientifique (CNRS)
Subjects: Materials science, Thorium, chemistry.chemical_element, Nanoparticle, 02 engineering and technology, Actinide, 010402 general chemistry, 021001 nanoscience & nanotechnology, 01 natural sciences, Nanocrystalline material, Silicate, 0104 chemical sciences, Thorite, Inorganic Chemistry, chemistry.chemical_compound, Actinides in the environment, chemistry, Chemical engineering, 13. Climate action, [CHIM]Chemical Sciences, 0210 nano-technology, ComputingMilieux_MISCELLANEOUS, Zircon
Abstract: Thorite, (ThSiO4) with a zircon type structure, is one of the most abundant natural sources of thorium on Earth. Generally, actinides are known to form nanoparticles in silicate medium, though no direct link between those colloids and the crystalline form of thorite was evidenced until now. Here we show the formation of thorite from colloids and nanocrystalline structures under experimental conditions close to environmental pH and temperature. Through in situ small and wide angle X-ray scattering (SWAXS) measurements, colloids with a few nanometers in size were first evidenced at a low reaction time. These colloids have elongated shapes and finally tend to aggregate after their size has reached 10 nm. Once aggregated, the system goes through a maturation step, ending with the emergence of nanocrystallites as thorite zircon structures. This maturation step is longer when the reaction temperature is decreased which highlights the kinetic considerations. These results have potential implications on the paragenesis of Th mineral deposits and also in the behaviour of Th and, by analogy, tetravalent actinides in the environment. The significant characteristics of this work are that Th-silicate colloids were demonstrated at low temperatures and a near neutral pH with long-term stability and a morphology in favor of high mobility in groundwater. If these species are formed in more diluted media, this could be problematic owing to the spreading of Th and, by analogy, other tetravalent actinides in the environment.
Published: 2020
Full Text: View/download PDF

13. The formation of PuSiO4 under hydrothermal conditions

Author: Paul Estevenon, Gauthier Jouan, Nicolas Dacheux, Philippe Moisy, Christelle Tamain, Stéphanie Szenknect, Christophe Poinssot, Eleonore Welcomme, Adel Mesbah, Département de recherche sur les procédés pour la mine et le recyclage du combustible (DMRC), CEA-Direction des Energies (ex-Direction de l'Energie Nucléaire) (CEA-DES (ex-DEN)), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA), Interfaces de Matériaux en Evolution (LIME), Institut de Chimie Séparative de Marcoule (ICSM - UMR 5257), Centre National de la Recherche Scientifique (CNRS)-Institut de Chimie du CNRS (INC)-Université de Montpellier (UM)-Ecole Nationale Supérieure de Chimie de Montpellier (ENSCM)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Centre National de la Recherche Scientifique (CNRS)-Institut de Chimie du CNRS (INC)-Université de Montpellier (UM)-Ecole Nationale Supérieure de Chimie de Montpellier (ENSCM)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA), and Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Ecole Nationale Supérieure de Chimie de Montpellier (ENSCM)-Institut de Chimie du CNRS (INC)-Université de Montpellier (UM)-Centre National de la Recherche Scientifique (CNRS)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Ecole Nationale Supérieure de Chimie de Montpellier (ENSCM)-Institut de Chimie du CNRS (INC)-Université de Montpellier (UM)-Centre National de la Recherche Scientifique (CNRS)
Subjects: Inorganic chemistry, chemistry.chemical_element, Thorium, Hydrochloric acid, 02 engineering and technology, Uranium, 010402 general chemistry, 021001 nanoscience & nanotechnology, 01 natural sciences, Silicate, Hydrothermal circulation, 0104 chemical sciences, Plutonium, Inorganic Chemistry, chemistry.chemical_compound, Cerium, chemistry, [CHIM]Chemical Sciences, 0210 nano-technology
Abstract: Attempts to synthesize plutonium(iv) silicate, PuSiO4, have been made on the basis of results recently reported in the literature for CeSiO4, ThSiO4, and USiO4 under hydrothermal conditions. Although it was not possible to prepare PuSiO4via applying the conditions reported for thorium and uranium, an efficient method of PuSiO4 synthesis was established by applying the conditions optimized for the CeSiO4 system. This method was based on the slow oxidation of plutonium(iii) silicate reactants under hydrothermal conditions at 150 °C in hydrochloric acid (pH = 3-4). These results shed new light on the potential behavior of plutonium in reductive environments, highlighting the representative nature of cerium surrogates when studying plutonium under such conditions and providing some important pieces of information regarding plutonium chemistry in silicate solutions.
Published: 2020
Full Text: View/download PDF

14. Guanidinium dioxidobis(picolinato-κ2N,O)(picolinato-κO)uranate(VI)

Author: Vitalii I. Mishkevich, Mikhail S. Grigoriev, Alexandre M. Fedosseev, and Philippe Moisy
Subjects: Crystallography, QD901-999
Abstract: In the title compound, (CH6N3)[U(C6H4NO2)3O2], the uranyl group is coordinated by two O and two N atoms from two chelating picolinate ligands, and one O atom from a third picolinate ligand. The coordination environment of the UVI atom (N2O5) is distorted pentagonal–bipyramidal. In the crystal, all amino groups are involved in the formation of N—H...O and N—H...N hydrogen bonds, which link cations and anions into layers parallel to the ac plane.
Published: 2012
Full Text: View/download PDF

15. Dihydrogen H$_2$ steady state in $\alpha$-radiolysis of water adsorbed on PuO$_2$ surface

Author: Jackie Vermeulen, Philippe Moisy, Nicolas Vigier, Jérémy Gaillard, Natalia Budanova, Laurent Venault, Arnaud Deroche, Olivier Lemaire, Jérôme Maurin, Département de recherche sur les procédés pour la mine et le recyclage du combustible (DMRC), CEA-Direction des Energies (ex-Direction de l'Energie Nucléaire) (CEA-DES (ex-DEN)), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA), ORANO, the Orano Group, CEA- Saclay (CEA), and Commissariat à l'énergie atomique et aux énergies alternatives (CEA)
Subjects: Radiation, Hydrogen, 010308 nuclear & particles physics, Kinetics, chemistry.chemical_element, Thermal treatment, 01 natural sciences, 030218 nuclear medicine & medical imaging, 03 medical and health sciences, 0302 clinical medicine, Adsorption, chemistry, 13. Climate action, Chemical physics, Specific surface area, 0103 physical sciences, Radiolysis, [CHIM]Chemical Sciences, Relative humidity, Hydrogen production
Abstract: International audience; Radiolysis of water adsorbed on PuO$_2$ surface has been the subject of several studies but still remains poorly understood. The present study brings new experimental results helping to further understand the phenomena occurring at PuO$_2$ surface. Radiolysis of adsorbed water on PuO2 surface leads to the reach of a steady state in hydrogen content when relative humidity is kept constant implying an equilibrium between generation and consumption of hydrogen. The influences of specific surface area, relative humidity, PuO$_2$ dose rate and composition of the atmosphere (Ar vs air) on hydrogen generation were investigated. A significant evolution of the hydrogen generation kinetics was observed upon PuO$_2$ surface aging. This result might be related to an evolution of the surface physicochemical state induced by a long-term storage in H$_2$O/H$_2$/O$_2$ atmosphere. The surface evolution modifies the equilibrium between generation and consumption of hydrogen. Several annealing thermal treatment were necessary to retrieve H$_2$ accumulations kinetics similar to the ones obtained with the same sample as freshly prepared. This indicates an important evolution of PuO$_2$ surface and subsurface. A mechanism is described to explain the surface evolution and its effect on H$_2$ accumulation through radiolysis of adsorbed water.
Published: 2019
Full Text: View/download PDF

16. Protactinium(V) in aqueous solution: a light actinide without actinyl moiety

Author: Christophe Den Auwer, Claire Le Naour, Philippe Moisy, Jean Aupiais, Jérôme Roques, Institut de Physique Nucléaire d'Orsay (IPNO), Université Paris-Sud - Paris 11 (UP11)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Centre National de la Recherche Scientifique (CNRS), Institut de Chimie de Nice (ICN), Université Nice Sophia Antipolis (1965 - 2019) (UNS), COMUE Université Côte d'Azur (2015-2019) (COMUE UCA)-COMUE Université Côte d'Azur (2015-2019) (COMUE UCA)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS)-Université Côte d'Azur (UCA), Département de recherche sur les procédés pour la mine et le recyclage du combustible (DMRC), CEA-Direction des Energies (ex-Direction de l'Energie Nucléaire) (CEA-DES (ex-DEN)), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA), DAM Île-de-France (DAM/DIF), Direction des Applications Militaires (DAM), Centre National de la Recherche Scientifique (CNRS)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Université Paris-Sud - Paris 11 (UP11), and Université Nice Sophia Antipolis (... - 2019) (UNS)
Subjects: Aqueous solution, 010405 organic chemistry, Inorganic chemistry, Protactinium, chemistry.chemical_element, Actinide, 010402 general chemistry, 01 natural sciences, 0104 chemical sciences, chemistry, Moiety, Physical and Theoretical Chemistry, [CHIM.OTHE]Chemical Sciences/Other, ComputingMilieux_MISCELLANEOUS
Abstract: This review highlights recent data on the complexation of Pa(V) with inorganic (fluoride and sulphate) and organic (oxalate, nitrilotriacetate, diethylenetriaminepentaacetate) ligands in solution. New thermodynamic parameters relative to the complexation of Pa(V) with sulphate are presented. The review also includes gas phase and theoretical studies focused on the interaction of Pa(V) in the dioxo and oxo forms with water.
Published: 2019
Full Text: View/download PDF

17. Formation of CeSiO 4 from cerium( iii ) silicate precursors

Author: Thibault Kaczmarek, Philippe Moisy, Eleonore Welcomme, Thomas Dumas, Adel Mesbah, Stéphanie Szenknect, Nicolas Dacheux, Paul Estevenon, Pier Lorenzo Solari, Christophe Poinssot, Fabien Vadot, Département de recherche sur les procédés pour la mine et le recyclage du combustible (DMRC), CEA-Direction des Energies (ex-Direction de l'Energie Nucléaire) (CEA-DES (ex-DEN)), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA), Interfaces de Matériaux en Evolution (LIME), Institut de Chimie Séparative de Marcoule (ICSM - UMR 5257), Centre National de la Recherche Scientifique (CNRS)-Institut de Chimie du CNRS (INC)-Université de Montpellier (UM)-Ecole Nationale Supérieure de Chimie de Montpellier (ENSCM)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Centre National de la Recherche Scientifique (CNRS)-Institut de Chimie du CNRS (INC)-Université de Montpellier (UM)-Ecole Nationale Supérieure de Chimie de Montpellier (ENSCM)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA), Synchrotron SOLEIL (SSOLEIL), Centre National de la Recherche Scientifique (CNRS), Commissariat à l'énergie atomique et aux énergies alternatives (CEA), and Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Ecole Nationale Supérieure de Chimie de Montpellier (ENSCM)-Institut de Chimie du CNRS (INC)-Université de Montpellier (UM)-Centre National de la Recherche Scientifique (CNRS)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Ecole Nationale Supérieure de Chimie de Montpellier (ENSCM)-Institut de Chimie du CNRS (INC)-Université de Montpellier (UM)-Centre National de la Recherche Scientifique (CNRS)
Subjects: In situ, Aqueous solution, 010405 organic chemistry, chemistry.chemical_element, Hydrothermal treatment, [CHIM.INOR]Chemical Sciences/Inorganic chemistry, 010402 general chemistry, 01 natural sciences, Silicate, Hydrothermal circulation, 0104 chemical sciences, Inorganic Chemistry, chemistry.chemical_compound, Cerium, chemistry, Hydrothermal synthesis, [CHIM]Chemical Sciences, [CHIM.RADIO]Chemical Sciences/Radiochemistry, ComputingMilieux_MISCELLANEOUS, Oxidation rate, Nuclear chemistry
Abstract: Although the preparation of CeSiO4 has been already reported, the formation of pure cerium silicate from aqueous precursors appears as a challenge. An innovative way of synthesis has been identified in this study, allowing the formation of CeSiO4 after hydrothermal treatment starting from Ce(iii) silicate precursors. Among the experimental parameters examined, significant effects were found according to the nature of the precursor and of the reactive media considered, the pH of the reactive media and the temperature of the hydrothermal process. This study allows the determination of optimized conditions for the hydrothermal synthesis of pure CeSiO4 (A-Ce2Si2O7 or Ce4.67(SiO4)3O as starting precursors, nitric medium, pH = 7, 7 days at 150 °C). The in situ low oxidation rate of Ce(iii) into Ce(iv) was a key parameter to consider in order to avoid the presence of CeO2 in the final mixtures.
Published: 2019
Full Text: View/download PDF

18. Deciphering the Crystal Structure of a Scarce 1D Polymeric Thorium Peroxo Sulfate

Author: Laura Bonato, Pierre Lecante, Sergey I. Nikitenko, Nicolas Dacheux, Thomas Dumas, Adel Mesbah, Philippe Moisy, Matthieu Virot, Damien Prieur, Xavier F. Le Goff, Christoph Hennig, Sonochimie dans les Fluides Complexes (LSFC), Institut de Chimie Séparative de Marcoule (ICSM - UMR 5257), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Centre National de la Recherche Scientifique (CNRS)-Ecole Nationale Supérieure de Chimie de Montpellier (ENSCM)-Université de Montpellier (UM)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Centre National de la Recherche Scientifique (CNRS)-Ecole Nationale Supérieure de Chimie de Montpellier (ENSCM)-Université de Montpellier (UM), Département de recherche sur les procédés pour la mine et le recyclage du combustible (DMRC), CEA-Direction des Energies (ex-Direction de l'Energie Nucléaire) (CEA-DES (ex-DEN)), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA), Interfaces de Matériaux en Evolution (LIME), Centre d'élaboration de matériaux et d'études structurales (CEMES), Institut National des Sciences Appliquées - Toulouse (INSA Toulouse), Institut National des Sciences Appliquées (INSA)-Institut National des Sciences Appliquées (INSA)-Institut de Chimie de Toulouse (ICT-FR 2599), Centre National de la Recherche Scientifique (CNRS)-Université Toulouse III - Paul Sabatier (UT3), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Institut de Recherche pour le Développement (IRD)-Institut National Polytechnique (Toulouse) (Toulouse INP), Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS)-Université Toulouse III - Paul Sabatier (UT3), Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS), JRC Institute for Transuranium Elements [Karlsruhe] (ITU ), European Commission - Joint Research Centre [Karlsruhe] (JRC), Etude de la Matière en Mode Environnemental (L2ME), Institute of Resource Ecology [Dresden] (IRE), Helmholtz-Zentrum Dresden-Rossendorf (HZDR), Service de Chimie des Procédés de Séparation (SCPS), Commissariat à l'énergie atomique et aux énergies alternatives (CEA), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Ecole Nationale Supérieure de Chimie de Montpellier (ENSCM)-Institut de Chimie du CNRS (INC)-Université de Montpellier (UM)-Centre National de la Recherche Scientifique (CNRS)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Ecole Nationale Supérieure de Chimie de Montpellier (ENSCM)-Institut de Chimie du CNRS (INC)-Université de Montpellier (UM)-Centre National de la Recherche Scientifique (CNRS), Institut National des Sciences Appliquées (INSA)-Université de Toulouse (UT)-Institut National des Sciences Appliquées (INSA)-Université de Toulouse (UT)-Institut de Chimie de Toulouse (ICT), Institut de Recherche pour le Développement (IRD)-Université Toulouse III - Paul Sabatier (UT3), Université de Toulouse (UT)-Université de Toulouse (UT)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS)-Institut National Polytechnique (Toulouse) (Toulouse INP), Université de Toulouse (UT)-Institut de Recherche pour le Développement (IRD)-Université Toulouse III - Paul Sabatier (UT3), Université de Toulouse (UT)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS)-Institut National Polytechnique (Toulouse) (Toulouse INP), Université de Toulouse (UT)-Centre National de la Recherche Scientifique (CNRS), European Synchrotron Radiation Facility (ESRF), Centre National de la Recherche Scientifique (CNRS)-Institut de Chimie du CNRS (INC)-Université de Montpellier (UM)-Ecole Nationale Supérieure de Chimie de Montpellier (ENSCM)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Centre National de la Recherche Scientifique (CNRS)-Institut de Chimie du CNRS (INC)-Université de Montpellier (UM)-Ecole Nationale Supérieure de Chimie de Montpellier (ENSCM)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA), Université Toulouse III - Paul Sabatier (UT3), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS)-Institut de Chimie de Toulouse (ICT-FR 2599), Institut National Polytechnique (Toulouse) (Toulouse INP), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD)-Université Toulouse III - Paul Sabatier (UT3), Université Fédérale Toulouse Midi-Pyrénées-Institut de Chimie du CNRS (INC)-Institut National Polytechnique (Toulouse) (Toulouse INP), Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD)-Institut de Chimie du CNRS (INC)-Institut National des Sciences Appliquées - Toulouse (INSA Toulouse), and Institut National des Sciences Appliquées (INSA)-Institut National des Sciences Appliquées (INSA)
Subjects: 010405 organic chemistry, Ligand, Organic Chemistry, Thorium, chemistry.chemical_element, General Chemistry, Crystal structure, Structure type, [CHIM.INOR]Chemical Sciences/Inorganic chemistry, 010402 general chemistry, 01 natural sciences, Peroxide, Catalysis, Synchrotron, 0104 chemical sciences, law.invention, chemistry.chemical_compound, Crystallography, chemistry, law, [CHIM.CRIS]Chemical Sciences/Cristallography, [CHIM]Chemical Sciences, Orthorhombic crystal system, Sulfate, [CHIM.RADIO]Chemical Sciences/Radiochemistry
Abstract: International audience; The preparation and structural characterization of an original Th peroxo sulfate dihydrate, crystallizing at room temperature in the form of stable 1D polymeric microfibres is described. A combination of laboratory and synchrotron techniques allowed solution of the structure of the Th(O2)(SO4)(H2O)2 compound, which crystallizes in a new structure type in the space group Pna21 of the orthorhombic crystal system. Particularly, the peroxide ligand coordinates to the Th cations in an unusual μ3‐η2:η2:η2 bridging mode, forming an infinite 1D chain decorated with sulfato ligands exhibiting simultaneously monodentate and bidentate coordination modes.
Published: 2019
Full Text: View/download PDF

19. Microsensing of plutonium with a glass optofluidic device

Author: Philippe Moisy, Davide Bucci, Fabrice Canto, Fabien Geoffray, Timothee Allenet, Jean-Emmanuel Broquin, Institut de Microélectronique, Electromagnétisme et Photonique - Laboratoire d'Hyperfréquences et Caractérisation (IMEP-LAHC ), Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP )-Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Centre National de la Recherche Scientifique (CNRS)-Université Grenoble Alpes [2016-2019] (UGA [2016-2019]), Commissariat à l'énergie atomique et aux énergies alternatives (CEA), Département de recherche sur les procédés pour la mine et le recyclage du combustible (DMRC), CEA-Direction des Energies (ex-Direction de l'Energie Nucléaire) (CEA-DES (ex-DEN)), and Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)
Subjects: Detection limit, Materials science, Borosilicate glass, business.industry, Calibration curve, Microfluidics, General Engineering, chemistry.chemical_element, 02 engineering and technology, Chip, 01 natural sciences, Atomic and Molecular Physics, and Optics, Optofluidics, Plutonium, 010309 optics, [SPI.ELEC]Engineering Sciences [physics]/Electromagnetism, 020210 optoelectronics & photonics, chemistry, 0103 physical sciences, 0202 electrical engineering, electronic engineering, information engineering, [SPI.OPTI]Engineering Sciences [physics]/Optics / Photonic, Optoelectronics, Absorption (electromagnetic radiation), business, ComputingMilieux_MISCELLANEOUS
Abstract: The cointegration of optical and microfluidic functions on chemically resilient borosilicate glass to provide microfluidic chemical analyses is described. An evanescent wave sensing chip containing a fluid channel of 21 μL is implemented to carry out absorption spectroscopy measurements in the near-infrared range. Microchip packaging allows to perform remote analysis of harsh chemical solutions in confined environments. Detection of plutonium(VI) in aqueous 1 mol/L nitric acid solutions is achieved on solutions ranging from 0.05 to 0.13 mol/L. Results showcase the validity of the proposed approach by obtaining a sensor calibration curve and chip resilience to highly concentrated strong acids and radioactive elements. This proof-of-concept opens the path to optimized devices with a lower limit of detection.
Published: 2019
Full Text: View/download PDF

20. Probing the Local Structure of Nanoscaled Actinide Oxides: A Comparison between PuO2 and ThO2 Nanoparticles Rules out PuO2+x Hypothesis

Author: Thierry Wiss, Laurent Venault, Philippe Moisy, Thomas Dumas, Adel Mesbah, Oliver Dieste Blanco, Matthieu Virot, Damien Prieur, Laura Bonato, Xavier F. Le Goff, Sergey I. Nikitenko, Elodie Dalodière, Michael Odorico, Nicolas Dacheux, André Rossberg, CEA, Contributeur MAP, Sonochimie dans les Fluides Complexes (LSFC), Institut de Chimie Séparative de Marcoule (ICSM - UMR 5257), Centre National de la Recherche Scientifique (CNRS)-Institut de Chimie du CNRS (INC)-Université de Montpellier (UM)-Ecole Nationale Supérieure de Chimie de Montpellier (ENSCM)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Centre National de la Recherche Scientifique (CNRS)-Institut de Chimie du CNRS (INC)-Université de Montpellier (UM)-Ecole Nationale Supérieure de Chimie de Montpellier (ENSCM)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA), Commissariat à l'énergie atomique et aux énergies alternatives (CEA), Northwestern University [Evanston], European Commission - Joint Research Centre [Karlsruhe] (JRC), Etude de la Matière en Mode Environnemental (L2ME), European Synchrotron Radiation Facility (ESRF), Département RadioChimie et Procédés (DRCP), CEA-Direction des Energies (ex-Direction de l'Energie Nucléaire) (CEA-DES (ex-DEN)), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA), Interfaces de Matériaux en Evolution (LIME), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Ecole Nationale Supérieure de Chimie de Montpellier (ENSCM)-Institut de Chimie du CNRS (INC)-Université de Montpellier (UM)-Centre National de la Recherche Scientifique (CNRS)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Ecole Nationale Supérieure de Chimie de Montpellier (ENSCM)-Institut de Chimie du CNRS (INC)-Université de Montpellier (UM)-Centre National de la Recherche Scientifique (CNRS), and Institut des Sciences et technologies pour une Economie Circulaire des énergies bas carbone (ISEC)
Subjects: [CHIM.INOR] Chemical Sciences/Inorganic chemistry, Materials science, Oxide, Nanoparticle, Bioengineering, 02 engineering and technology, [CHIM.INOR]Chemical Sciences/Inorganic chemistry, 010402 general chemistry, 01 natural sciences, Colloid, chemistry.chemical_compound, [CHIM.RADIO] Chemical Sciences/Radiochemistry, [CHIM.CRIS]Chemical Sciences/Cristallography, General Materials Science, Reactivity (chemistry), [CHIM.CRIS] Chemical Sciences/Cristallography, ComputingMilieux_MISCELLANEOUS, [CHIM.MATE] Chemical Sciences/Material chemistry, Extended X-ray absorption fine structure, General Engineering, [CHIM.MATE]Chemical Sciences/Material chemistry, General Chemistry, Actinide, 021001 nanoscience & nanotechnology, Atomic and Molecular Physics, and Optics, 0104 chemical sciences, Characterization (materials science), Nanocrystal, chemistry, Chemical physics, 0210 nano-technology, [CHIM.RADIO]Chemical Sciences/Radiochemistry
Abstract: International audience; Actinide research at the nanoscale is gaining fundamental interest due to environmental and industrial issues. The knowledge of the local structure and speciation of actinide nanoparticles, which possibly exhibit specific physico-chemical properties in comparison to bulk materials, would help in a better and reliable description of their behaviour and reactivity. Herein, the synthesis and relevant characterization of PuO2 and ThO2 nanoparticles displayed as dispersed colloids, nanopowders or nanostructured oxide powders, allow to establish a clear relationship between the size of the nanocrystals composing these oxides and their corresponding An(IV) local structure investigated by EXAFS spectroscopy. Particularly, the probed An(IV) first oxygen shell evidences an analogous behaviour for both Pu and Th oxides. This observation suggests that the often observed and controversial splitting of the Pu-O shell on the Fourier transformed EXAFS signal of PuO2 samples is attributed to a local structural disorder driven by a nanoparticle surface effect rather than to the presence of PuO2+x species.
Published: 2019
Full Text: View/download PDF

21. Is hydroxypyridonate 3,4,3-LI(1,2-HOPO) a good competitor of fetuin for uranyl metabolism?

Author: Maria Rosa Beccia, Christophe Den Auwer, Philippe Moisy, Jérôme Roques, Claude Vidaud, Ali Younes, Pier Lorenzo Solari, Gaëlle Creff, Christoph Hennig, Jean Aupiais, Laboratoire d'Etudes du Comportement à Long Terme des matériaux de conditionnement (LCLT), Département de recherche sur les technologies pour l'enrichissement, le démantèlement et les déchets (DE2D), CEA-Direction des Energies (ex-Direction de l'Energie Nucléaire) (CEA-DES (ex-DEN)), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-CEA-Direction des Energies (ex-Direction de l'Energie Nucléaire) (CEA-DES (ex-DEN)), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA), Institut de Chimie de Nice (ICN), Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS)-Université Côte d'Azur (UCA)-Université Nice Sophia Antipolis (... - 2019) (UNS), COMUE Université Côte d'Azur (2015-2019) (COMUE UCA)-COMUE Université Côte d'Azur (2015-2019) (COMUE UCA), Institut de Physique Nucléaire d'Orsay (IPNO), Centre National de la Recherche Scientifique (CNRS)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Université Paris-Sud - Paris 11 (UP11), Direction des Applications Militaires (DAM), Commissariat à l'énergie atomique et aux énergies alternatives (CEA), European Synchrotron Radiation Facility (ESRF), Synchrotron SOLEIL (SSOLEIL), Centre National de la Recherche Scientifique (CNRS), Université Nice Sophia Antipolis (... - 2019) (UNS), COMUE Université Côte d'Azur (2015-2019) (COMUE UCA)-COMUE Université Côte d'Azur (2015-2019) (COMUE UCA)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS)-Université Côte d'Azur (UCA), Université Côte d'Azur (UCA)-Université Côte d'Azur (UCA)-Centre National de la Recherche Scientifique (CNRS), Université Paris-Sud - Paris 11 (UP11)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Centre National de la Recherche Scientifique (CNRS), Département de recherche sur les Procédés et Matériaux pour les Environnements complexes (DPME), and Université Nice Sophia Antipolis (1965 - 2019) (UNS)
Subjects: 0301 basic medicine, Pyridones, Biophysics, Biochemistry, Biomaterials, 03 medical and health sciences, chemistry.chemical_compound, Heterocyclic Compounds, 1-Ring, Effective treatment, Molecule, Animals, Humans, Chelation, Fetuins, Chelating Agents, [PHYS]Physics [physics], 030102 biochemistry & molecular biology, Molecular Structure, Metals and Alloys, Metabolism, Uranyl, Fetuin, In vitro, 030104 developmental biology, chemistry, Chemistry (miscellaneous), Uranium, Biomineralization
Abstract: International audience; Uranium is widespread in the environment, resulting both from natural occurrences and anthropogenic activities. Its toxicity is mainly chemical rather than radiological. In the blood it is transported as uranyl UO22+ cation and forms complexes with small ligands like carbonates and with some proteins. From there it reaches the skeleton, its main target organ for accumulation. Fetuin is a serum protein involved in biomineralization processes, and it was demonstrated to be the main UO22+-binder in vitro. Fetuin's life cycle ends in bone. It is thus suspected to be a key protagonist of U accumulation in this organ. Up to now, there has been no effective treatment for the removal of U from the body and studies devoted to the interactions involving chelating agents with both UO22+ and its protein targets are lacking. The present work aims at studying the potential role of 3,4,3-LI(1,2-HOPO) as a promising chelating agent in competition with fetuin. The apparent affinity constant of 3,4,3-LI(1,2-HOPO) was first determined, giving evidence for its very high affinity similar to that of fetuin. Chromatography experiments, aimed at identifying the complexes formed and quantifying their UO22+ content, and spectroscopic structural investigations (XAS) were carried out, demonstrating that 3,4,3-LI(1,2-HOPO) inhibits/limits the formation of fetuin–uranyl complexes under stoichiometric conditions. But surprisingly, possible ternary complexes stable enough to remain present after the chromatographic process were identified under sub-stoichiometric conditions of HOPO versus fetuin. These results contribute to the understanding of the mechanisms accounting for U residual accumulation despite chelation therapy after internal contamination.
Published: 2019
Full Text: View/download PDF

22. Insight of the metal-ligand interaction in f elements complexes by paramagnetic NMR spectroscopy

Author: Mikhail S. Grigoriev, Matthieu Autillo, Pier Lorenzo Solari, Hélène Bolvin, Sebastiano Cammelli, Alexandre M. Fedoseev, Dominique Guillaumont, Philippe Guilbaud, Thomas Dumas, Laetitia Guerin, Philippe Moisy, Claude Berthon, CEA-Direction des Energies (ex-Direction de l'Energie Nucléaire) (CEA-DES (ex-DEN)), Commissariat à l'énergie atomique et aux énergies alternatives (CEA), Russian Academy of Sciences [Moscow] (RAS), Synchrotron SOLEIL (SSOLEIL), Centre National de la Recherche Scientifique (CNRS), Laboratoire de Chimie et Physique Quantiques (LCPQ), Institut de Recherche sur les Systèmes Atomiques et Moléculaires Complexes (IRSAMC), Université Toulouse III - Paul Sabatier (UT3), Université de Toulouse (UT)-Université de Toulouse (UT)-Centre National de la Recherche Scientifique (CNRS)-Université Toulouse III - Paul Sabatier (UT3), Université de Toulouse (UT)-Université de Toulouse (UT)-Centre National de la Recherche Scientifique (CNRS)-Institut de Chimie du CNRS (INC), Systèmes étendus et magnétisme (LCPQ) (SEM), Université de Toulouse (UT)-Université de Toulouse (UT)-Centre National de la Recherche Scientifique (CNRS)-Institut de Chimie du CNRS (INC)-Institut de Recherche sur les Systèmes Atomiques et Moléculaires Complexes (IRSAMC), ANR-17-CE06-0010,ACTIpNMR,déplacements de RMN paramagnétiques pour les actinides : au délà du modèle des lanthanides(2017), CEA Nuclear Energy Division, A.N. Frumkin Institute of Physical Chemistry and Electrochemistry, Institut National des Sciences Appliquées - Toulouse (INSA Toulouse), Institut National des Sciences Appliquées (INSA)-Institut National des Sciences Appliquées (INSA)-Université Toulouse III - Paul Sabatier (UT3), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS)-Institut National des Sciences Appliquées - Toulouse (INSA Toulouse), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS)-Institut de Chimie du CNRS (INC)-Institut de Recherche sur les Systèmes Atomiques et Moléculaires Complexes (IRSAMC), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS)-Institut de Chimie du CNRS (INC), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS)-Université Toulouse III - Paul Sabatier (UT3), Institut National des Sciences Appliquées (INSA)-Institut National des Sciences Appliquées (INSA)-Centre National de la Recherche Scientifique (CNRS)-Université Toulouse III - Paul Sabatier (UT3), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Institut National des Sciences Appliquées - Toulouse (INSA Toulouse), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Institut de Chimie du CNRS (INC)-Institut de Recherche sur les Systèmes Atomiques et Moléculaires Complexes (IRSAMC), and Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Institut de Chimie du CNRS (INC)
Subjects: Lanthanide, lanthanide, [PHYS.NUCL]Physics [physics]/Nuclear Theory [nucl-th], Bleaney, [PHYS.NEXP]Physics [physics]/Nuclear Experiment [nucl-ex], 010402 general chemistry, 01 natural sciences, Catalysis, paramagnetism, Paramagnetism, Ab initio quantum chemistry methods, Hyperfine structure, ComputingMilieux_MISCELLANEOUS, Extended X-ray absorption fine structure, 010405 organic chemistry, Chemistry, actinide, Organic Chemistry, General Chemistry, Nuclear magnetic resonance spectroscopy, NMR, 0104 chemical sciences, NMR spectra database, [CHIM.THEO]Chemical Sciences/Theoretical and/or physical chemistry, Crystallography, Magnetic anisotropy
Abstract: The magnetic properties of LnIII and AnIII complexes formed with dipicolinate ligands have been studied by NMR spectroscopy. To know precisely the geometries of these complexes, a crystallographic study by single-crystal X-ray diffraction (XRD) and extended X-ray absorption fine structure (EXAFS) in solution was performed. Several methods to separate the paramagnetic shifts observed in the NMR spectra were applied to these complexes. Methods using a number of nuclei of the dipicolinate ligands revealed an abrupt change in the geometries of the complexes and a metal-ligand interaction in the middle of the lanthanide series. A study of the variation of the paramagnetic shifts with temperature demonstrated that higher-order terms of the dipolar and contact contributions are required, especially for the lightest LnIII and almost all the studied AnIII . Bleaney's parameters a and C a D relating to the contact and dipolar terms, respectively, were deduced from experimental data and compared with the results of ab initio calculations. Quite a good agreement was found for the temperature dependencies of a and C a D . However, the C a D values obtained from cation magnetic anisotropy calculations showed some discrepancies with the values derived from Bleaney's equation defined for LnIII . Other parameters, such as the crystal field parameter and the hyperfine constants Fi obtained from the experimental data of the [An(ethyl-dpa)3 ]3- complexes (ethyl-dpa=4-ethyl-2,6-dipicolinic acid), are at odds with the assumptions underlying Bleaney's theory.
Published: 2019
Full Text: View/download PDF

23. Kinetics of dissolution of Th0.25U0.75O2 sintered pellets in various acidic conditions

Author: Philippe Moisy, Adel Mesbah, Thomas Dalger, Florent Tocino, Nicolas Dacheux, Stéphanie Szenknect, Laurent Claparede, Interfaces de Matériaux en Evolution (LIME), Institut de Chimie Séparative de Marcoule (ICSM - UMR 5257), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Ecole Nationale Supérieure de Chimie de Montpellier (ENSCM)-Institut de Chimie du CNRS (INC)-Université de Montpellier (UM)-Centre National de la Recherche Scientifique (CNRS)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Ecole Nationale Supérieure de Chimie de Montpellier (ENSCM)-Institut de Chimie du CNRS (INC)-Université de Montpellier (UM)-Centre National de la Recherche Scientifique (CNRS), CEA/Marcoule, Commissariat à l'énergie atomique et aux énergies alternatives (CEA), and Centre National de la Recherche Scientifique (CNRS)-Institut de Chimie du CNRS (INC)-Université de Montpellier (UM)-Ecole Nationale Supérieure de Chimie de Montpellier (ENSCM)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Centre National de la Recherche Scientifique (CNRS)-Institut de Chimie du CNRS (INC)-Université de Montpellier (UM)-Ecole Nationale Supérieure de Chimie de Montpellier (ENSCM)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)
Subjects: Nuclear and High Energy Physics, Kinetics, Inorganic chemistry, Hydrochloric acid, Sulfuric acid, 02 engineering and technology, [CHIM.MATE]Chemical Sciences/Material chemistry, [CHIM.INOR]Chemical Sciences/Inorganic chemistry, 021001 nanoscience & nanotechnology, 010403 inorganic & nuclear chemistry, 01 natural sciences, 0104 chemical sciences, chemistry.chemical_compound, Adsorption, Nuclear Energy and Engineering, chemistry, Nitric acid, Desorption, Specific surface area, [CHIM]Chemical Sciences, General Materials Science, 0210 nano-technology, Dissolution, ComputingMilieux_MISCELLANEOUS
Abstract: In order to gain insights into the kinetics of dissolution of Gen(IV) MOX fuels, sintered pellets of Th0.25U0.75O2 were prepared as surrogates. The study of the kinetics of dissolution was achieved to determine the impact of the incorporation of 25 mol % of thorium in UO2 on the rate and on the mechanism of dissolution. Especially, various acidic media were used to evidence changes occurring in the rate of the limiting step and to establish specific rate laws. For most of the investigated dissolution media the dissolution reaction was found to be congruent. The homogeneity of the Th0.25U0.75O2 solid/solutions allowed both elements to be recovered at the same rate. The way of synthesis by oxalate co-precipitation, then conversion in mixed oxide, allowed the quantitative dissolution of the elements. In aerated hydrochloric acid solutions, the kinetics of the overall dissolution reaction appeared to be controlled by adsorption and desorption of protons on activated surface sites. The dissolution rate determined in aerated sulfuric acid solution was enhanced compared to hydrochloric acid solution of the same acidity. This result was interpreted in terms of formation of sulfate ions surface complexes that favor the detachment of the actinides from the mixed oxide solid solution. In nitric acid solutions, the dissolution of the Th0.25U0.75O2 pellets followed several successive steps. During this first steady state period, the kinetics of the overall dissolution reaction appeared to be controlled by the oxidation of U(IV) by HNO3 at the solid/solution interface. A rate law was established by adding a redox contribution to the proton-promoted surface contribution defined for aerated hydrochloric acid solutions. Then, an increase of the normalized dissolution rate was observed, which was attributed to the simultaneous increase of the specific surface area of the pellet and of the HNO2 concentration in solution.
Published: 2018
Full Text: View/download PDF

24. The electronic structure of f-element Prussian blue analogs determined by soft X-ray absorption spectroscopy

Author: Pier Lorenzo Solari, Christophe Den Auwer, David K. Shuh, Philippe Moisy, Dominique Guillaumont, Thomas Dumas, Tolek Tyliszczak, CEA-Direction des Energies (ex-Direction de l'Energie Nucléaire) (CEA-DES (ex-DEN)), Commissariat à l'énergie atomique et aux énergies alternatives (CEA), Lawrence Berkeley National Laboratory [Berkeley] (LBNL), Synchrotron SOLEIL (SSOLEIL), and Centre National de la Recherche Scientifique (CNRS)
Subjects: Lanthanide, Materials science, Absorption spectroscopy, f-element, [PHYS.NUCL]Physics [physics]/Nuclear Theory [nucl-th], Metal ions in aqueous solution, Intermetallic, [PHYS.NEXP]Physics [physics]/Nuclear Experiment [nucl-ex], 010402 general chemistry, 01 natural sciences, Catalysis, chemistry.chemical_compound, Molecular solid, Materials Chemistry, Isostructural, Prussian blue, Valence (chemistry), 010405 organic chemistry, Organic Chemistry, Metals and Alloys, X-ray absorption spectroscopy, General Chemistry, 0104 chemical sciences, Surfaces, Coatings and Films, Electronic, Optical and Magnetic Materials, Crystallography, chemistry, Chemical Sciences, Ceramics and Composites
Abstract: International audience; In molecular solids derived from Prussian blue, intermetallic charge transfer is fostered through a cyano bridge two metal ions. In this study, isostructural trivalent lanthanide and tetravalent actinide Prussian blue analogs’ valence orbitals are probed by soft X-ray absorption measurements.
Published: 2018
Full Text: View/download PDF

25. Impact of Carbonate Ions on the Synthesis of ThSiO 4 under Hydrothermal Conditions

Author: Stéphanie Szenknect, Eleonore Welcomme, Adel Mesbah, Nicolas Dacheux, Paul Estevenon, Christophe Poinssot, Philippe Moisy, Département de recherche sur les procédés pour la mine et le recyclage du combustible (DMRC), CEA-Direction des Energies (ex-Direction de l'Energie Nucléaire) (CEA-DES (ex-DEN)), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA), Commissariat à l'énergie atomique et aux énergies alternatives (CEA), Interfaces de Matériaux en Evolution (LIME), Institut de Chimie Séparative de Marcoule (ICSM - UMR 5257), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Ecole Nationale Supérieure de Chimie de Montpellier (ENSCM)-Institut de Chimie du CNRS (INC)-Université de Montpellier (UM)-Centre National de la Recherche Scientifique (CNRS)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Ecole Nationale Supérieure de Chimie de Montpellier (ENSCM)-Institut de Chimie du CNRS (INC)-Université de Montpellier (UM)-Centre National de la Recherche Scientifique (CNRS), CEA/Marcoule, and Centre National de la Recherche Scientifique (CNRS)-Institut de Chimie du CNRS (INC)-Université de Montpellier (UM)-Ecole Nationale Supérieure de Chimie de Montpellier (ENSCM)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Centre National de la Recherche Scientifique (CNRS)-Institut de Chimie du CNRS (INC)-Université de Montpellier (UM)-Ecole Nationale Supérieure de Chimie de Montpellier (ENSCM)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)
Subjects: 010405 organic chemistry, Inorganic chemistry, Thorium, chemistry.chemical_element, [CHIM.MATE]Chemical Sciences/Material chemistry, [CHIM.INOR]Chemical Sciences/Inorganic chemistry, 010402 general chemistry, 01 natural sciences, Hydrothermal circulation, Silicate, 0104 chemical sciences, Thorite, Inorganic Chemistry, chemistry.chemical_compound, chemistry, 13. Climate action, Phase (matter), [CHIM.CRIS]Chemical Sciences/Cristallography, Carbonate, Hydrothermal synthesis, [CHIM]Chemical Sciences, Physical and Theoretical Chemistry, Solubility, [CHIM.RADIO]Chemical Sciences/Radiochemistry, ComputingMilieux_MISCELLANEOUS
Abstract: Multiparametric study of the hydrothermal synthesis of thorite, ThSiO4, was performed with the aim to determine the most efficient conditions to form single phase thorite samples. Among the experimental parameters investigated, temperature of the hydrothermal process, concentration of carbonate ions, thorium and silicon reactants, and pH of the reactive media significantly affect the composition of the final system obtained. Single phase samples of ThSiO4 were prepared in weakly basic reactive media and at temperatures over 150 °C, for thorium and silicate concentrations higher than 8 × 10-3 mol L-1 and carbonate concentrations of at least 8 × 10-2 mol L-1. Although the synthesis of thorite in carbonate media was already described in the literature, this study gives new insights to explain the key role of carbonate ions in the preparation of thorite. Especially, beyond their simple role of pH buffer, carbonate ions are involved in the formation of thorium-carbonate complexes at high pH, increasing the apparent solubility of thorium in weakly basic media. The presence of carbonate ions has an important impact not only on the domain of formation of thorite but also on the morphology of the silicate phase.
Published: 2018
Full Text: View/download PDF

26. Electrochemical behavior of platinum and gold electrodes in the aprotic ionic liquid N , N -Trimethylbutylammonium Bis(trifluoromethanesulfonyl)imide

Author: David Bengio, Philippe Moisy, Stéphane Pellet-Rostaing, Eric Mendes, Département de recherche sur les procédés pour la mine et le recyclage du combustible (DMRC), CEA-Direction des Energies (ex-Direction de l'Energie Nucléaire) (CEA-DES (ex-DEN)), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA), Tri ionique par les Systèmes Moléculaires auto-assemblés (LTSM), Institut de Chimie Séparative de Marcoule (ICSM - UMR 5257), Centre National de la Recherche Scientifique (CNRS)-Institut de Chimie du CNRS (INC)-Université de Montpellier (UM)-Ecole Nationale Supérieure de Chimie de Montpellier (ENSCM)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Centre National de la Recherche Scientifique (CNRS)-Institut de Chimie du CNRS (INC)-Université de Montpellier (UM)-Ecole Nationale Supérieure de Chimie de Montpellier (ENSCM)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA), and Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Ecole Nationale Supérieure de Chimie de Montpellier (ENSCM)-Institut de Chimie du CNRS (INC)-Université de Montpellier (UM)-Centre National de la Recherche Scientifique (CNRS)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Ecole Nationale Supérieure de Chimie de Montpellier (ENSCM)-Institut de Chimie du CNRS (INC)-Université de Montpellier (UM)-Centre National de la Recherche Scientifique (CNRS)
Subjects: General Chemical Engineering, Inorganic chemistry, chemistry.chemical_element, 02 engineering and technology, [CHIM.MATE]Chemical Sciences/Material chemistry, Chronoamperometry, 010402 general chemistry, 021001 nanoscience & nanotechnology, Electrochemistry, 01 natural sciences, 0104 chemical sciences, Analytical Chemistry, chemistry.chemical_compound, Adsorption, chemistry, Desorption, Ionic liquid, 0210 nano-technology, Imide, Platinum, Voltammetry, ComputingMilieux_MISCELLANEOUS
Abstract: The behavior of platinum and gold electrodes in the hydrophobic room-temperature ionic liquid (RTIL) N,N-Trimethylbutylammonium Bis(trifluoromethanesulfonyl)imide ([N4111][NTf2]) was investigated using transient electrochemistry e.g. voltammetry and chronoamperometry. As previously observed and contrary to what is often stated, these electrodes are not inert in the electroactivity domain of the solvent, between −3.0 and 2.7 V vs Fc/Fc+ for this RTIL. Indeed, a two-step oxidation of the platinum surface is observed at potentials higher than 1.0 V vs Fc/Fc+. The platinum oxide formed is reduced on reverse scan. Moreover, water being ubiquitous in ionic liquids, we can observe the oxidation of residual water and formation of O2. These processes both generate protons and lead to an activated state of the platinum surface. As a consequence, various signals around 0 V vs Fc/Fc+ can be attributed to the adsorption/desorption of protons and subsequent reduction to H2. In presence of water or HNTf2, this signal is enhanced. The behavior is very similar on a gold electrode but shows some specificity, particularly when it comes to the hydrogen evolution reaction.
Published: 2018
Full Text: View/download PDF

27. Multiparametric Study of the Synthesis of ThSiO 4 under Hydrothermal Conditions

Author: Adel Mesbah, Christophe Poinssot, Eleonore Welcomme, Nicolas Dacheux, Philippe Moisy, Stéphanie Szenknect, Paul Estevenon, Département de recherche sur les procédés pour la mine et le recyclage du combustible (DMRC), CEA-Direction des Energies (ex-Direction de l'Energie Nucléaire) (CEA-DES (ex-DEN)), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA), Commissariat à l'énergie atomique et aux énergies alternatives (CEA), Interfaces de Matériaux en Evolution (LIME), Institut de Chimie Séparative de Marcoule (ICSM - UMR 5257), Centre National de la Recherche Scientifique (CNRS)-Institut de Chimie du CNRS (INC)-Université de Montpellier (UM)-Ecole Nationale Supérieure de Chimie de Montpellier (ENSCM)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Centre National de la Recherche Scientifique (CNRS)-Institut de Chimie du CNRS (INC)-Université de Montpellier (UM)-Ecole Nationale Supérieure de Chimie de Montpellier (ENSCM)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA), CEA/Marcoule, and Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Ecole Nationale Supérieure de Chimie de Montpellier (ENSCM)-Institut de Chimie du CNRS (INC)-Université de Montpellier (UM)-Centre National de la Recherche Scientifique (CNRS)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Ecole Nationale Supérieure de Chimie de Montpellier (ENSCM)-Institut de Chimie du CNRS (INC)-Université de Montpellier (UM)-Centre National de la Recherche Scientifique (CNRS)
Subjects: Chemistry, 02 engineering and technology, [CHIM.MATE]Chemical Sciences/Material chemistry, [CHIM.INOR]Chemical Sciences/Inorganic chemistry, 010402 general chemistry, 021001 nanoscience & nanotechnology, 01 natural sciences, Hydrothermal circulation, 0104 chemical sciences, Thorite, Inorganic Chemistry, Chemical engineering, [CHIM.CRIS]Chemical Sciences/Cristallography, Hydrothermal synthesis, [CHIM]Chemical Sciences, Physical and Theoretical Chemistry, 0210 nano-technology, ComputingMilieux_MISCELLANEOUS
Abstract: A multiparametric study of the hydrothermal synthesis of ThSiO4, thorite, was performed with the aim of determining the most efficient conditions to form single-phase samples. Among the experimenta...
Published: 2018
Full Text: View/download PDF

28. Structural and magnetic susceptibility characterization of Pu(V) aqua ion using sonochemistry as a facile synthesis method

Author: Thomas Dumas, Marie-Claire Illy, Claude Berthon, Laurent Venault, André Rossberg, Philippe Moisy, Matthieu Virot, Laetitia Guerin, Sergey I. Nikitenko, Elodie Dalodière, Dominique Guillaumont, Sonochimie dans les Fluides Complexes (LSFC), Institut de Chimie Séparative de Marcoule (ICSM - UMR 5257), Centre National de la Recherche Scientifique (CNRS)-Institut de Chimie du CNRS (INC)-Université de Montpellier (UM)-Ecole Nationale Supérieure de Chimie de Montpellier (ENSCM)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Centre National de la Recherche Scientifique (CNRS)-Institut de Chimie du CNRS (INC)-Université de Montpellier (UM)-Ecole Nationale Supérieure de Chimie de Montpellier (ENSCM)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA), Département de recherche sur les procédés pour la mine et le recyclage du combustible (DMRC), CEA-Direction des Energies (ex-Direction de l'Energie Nucléaire) (CEA-DES (ex-DEN)), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA), European Synchrotron Radiation Facility (ESRF), and Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Ecole Nationale Supérieure de Chimie de Montpellier (ENSCM)-Institut de Chimie du CNRS (INC)-Université de Montpellier (UM)-Centre National de la Recherche Scientifique (CNRS)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Ecole Nationale Supérieure de Chimie de Montpellier (ENSCM)-Institut de Chimie du CNRS (INC)-Université de Montpellier (UM)-Centre National de la Recherche Scientifique (CNRS)
Subjects: Aqueous solution, Absorption spectroscopy, Extended X-ray absorption fine structure, Chemistry, Disproportionation, 02 engineering and technology, [CHIM.MATE]Chemical Sciences/Material chemistry, 010402 general chemistry, 021001 nanoscience & nanotechnology, 01 natural sciences, Magnetic susceptibility, 0104 chemical sciences, X-ray absorption fine structure, Sonochemistry, Inorganic Chemistry, Physical chemistry, Curie constant, 0210 nano-technology, ComputingMilieux_MISCELLANEOUS, Nuclear chemistry
Abstract: Since the past few years, Pu(V) has gained much attention due to its potential contribution to the environmental migration of actinides. However, the preparation of concentrated (up to mM) and pure Pu(V) solutions is quite difficult and often hindered by its great instability towards disproportionation, thus limiting the accessibility to physical and chemical property data. This work describes the rapid and facile sonochemical preparation of relatively stable Pu(V) solutions in the millimolar range free from the admixtures of the other oxidation states of plutonium. The mechanism deals with the sonochemical reduction of Pu(VI) in weakly acidic perchloric solutions by using the in situ generated H2O2, where the kinetics can be dramatically enhanced under high frequency ultrasound and an Ar/O2 atmosphere. The quasi-exclusive presence of the Pu(V) aqua ion in solution was evidenced by UV-vis absorption spectroscopy. The prepared solutions were found to be stable for more than one month which allowed the accurate XAFS and NMR investigations of Pu(V). EXAFS spectra revealed the presence of two trans dioxo Pu[double bond, length as m-dash]O bonds at 1.81 Å and 4–6 equatorial Pu–Oeq interactions at 2.47 Å characteristic of coordinated water molecules. The exact number of water molecules (N[Oeq(H2O)] = 4) was determined by simulating the EXAFS spectra of the PuO2+ aqua complexes using DFT calculations (geometry and the Debye–Waller factor) and comparing them with experimental signals. For the first time, the magnetic susceptibility of the pentavalent state of plutonium in aqueous solutions was also determined (χM = 16.3 × 10−9 m3 mol−1 at 25 °C) and the related Curie constant was estimated (C = 6.896 × 10−6 m3 K mol−1).
Published: 2018
Full Text: View/download PDF

29. Solvent Extraction Investigations on Pu(IV) and Th(IV) Complexes with Hydrophilic SO3-Ph-BTP and SO3-Ph-BTBP Ligands

Author: Marie-Christine Charbonnel, Jerzy Narbutt, Philippe Moisy, Łukasz Steczek, CEA-Direction de l'Energie Nucléaire (CEA-DEN), Commissariat à l'énergie atomique et aux énergies alternatives (CEA), National Institute of Science and Technology (INCT), and CEA-Direction des Energies (ex-Direction de l'Energie Nucléaire) (CEA-DES (ex-DEN))
Subjects: BTBP, complexes, [PHYS.NUCL]Physics [physics]/Nuclear Theory [nucl-th], General Chemical Engineering, 02 engineering and technology, General Chemistry, [PHYS.NEXP]Physics [physics]/Nuclear Experiment [nucl-ex], 010403 inorganic & nuclear chemistry, 01 natural sciences, solvent extraction, 0104 chemical sciences, thorium, stability constants, Bipyridine, chemistry.chemical_compound, 020401 chemical engineering, chemistry, Plutonium(IV), 0204 chemical engineering, Solvent extraction, hydrophilic ligands, Nuclear chemistry
Abstract: International audience; Complexation of Pu(IV) and Th(IV) cations by the title ligands hydrophilic triazinyl derivatives of pyridine and bipyridine was studied by solvent extraction with TODGA. Stoichiometries and stability constants of the complexes in the aqueous phase have been determined, the Pu(IV) complexes being significantly stronger than their Th(IV) analogues. Only two kinds (11 and 12) of the complexes with SO3 Ph BTP have been detected, and only one kind (11) with SO3 Ph BTBP. These numbers are lower than those expected based on the coordination numbers of the metal ions and on the denticities of the ligands. Possible reasons of this discrepancy were discussed.
Published: 2018
Full Text: View/download PDF

30. Insights into the sonochemical synthesis and properties of salt-free intrinsic plutonium colloids

Author: David K. Shuh, Philippe Moisy, Oliver Dieste Blanco, Vincent Morosini, Thomas Dumas, Laurent Venault, Tony Chave, Christoph Hennig, Sergey I. Nikitenko, Elodie Dalodière, Matthieu Virot, Thierry Wiss, Tolek Tyliszcak, Sonochimie dans les Fluides Complexes (LSFC), Institut de Chimie Séparative de Marcoule (ICSM - UMR 5257), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Ecole Nationale Supérieure de Chimie de Montpellier (ENSCM)-Institut de Chimie du CNRS (INC)-Université de Montpellier (UM)-Centre National de la Recherche Scientifique (CNRS)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Ecole Nationale Supérieure de Chimie de Montpellier (ENSCM)-Institut de Chimie du CNRS (INC)-Université de Montpellier (UM)-Centre National de la Recherche Scientifique (CNRS), Analyse, Géométrie et Modélisation (AGM - UMR 8088), Centre National de la Recherche Scientifique (CNRS)-CY Cergy Paris Université (CY), European Synchrotron Radiation Facility (ESRF), European Commission - Joint Research Centre [Karlsruhe] (JRC), Lawrence Berkeley National Laboratory [Berkeley] (LBNL), Advanced Light Source [LBNL Berkeley] (ALS), Département de recherche sur les procédés pour la mine et le recyclage du combustible (DMRC), CEA-Direction des Energies (ex-Direction de l'Energie Nucléaire) (CEA-DES (ex-DEN)), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA), European Project: 323300,EC:FP7:Fission,FP7-Fission-2012,TALISMAN(2013), and Centre National de la Recherche Scientifique (CNRS)-Institut de Chimie du CNRS (INC)-Université de Montpellier (UM)-Ecole Nationale Supérieure de Chimie de Montpellier (ENSCM)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Centre National de la Recherche Scientifique (CNRS)-Institut de Chimie du CNRS (INC)-Université de Montpellier (UM)-Ecole Nationale Supérieure de Chimie de Montpellier (ENSCM)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)
Subjects: X-ray absorption spectroscopy, Multidisciplinary, digestive, oral, and skin physiology, Kinetics, chemistry.chemical_element, Nanoparticle, 02 engineering and technology, [CHIM.MATE]Chemical Sciences/Material chemistry, 010402 general chemistry, 021001 nanoscience & nanotechnology, Pu(IV) colloids, 01 natural sciences, Article, XANES, 0104 chemical sciences, Plutonium, Other Physical Sciences, Colloid, chemistry, Chemical engineering, Water splitting, Biochemistry and Cell Biology, sonochemistry, 0210 nano-technology, High-resolution transmission electron microscopy
Abstract: For the first time, stable intrinsic plutonium colloid was prepared by ultrasonic treatment of PuO2 suspensions in pure water at room temperature. The yield of Pu colloid was found to increase with PuO2 specific surface area and by using reducing carrier gas mixture. Kinetic data evidenced that both chemical and mechanical effects of ultrasound strongly contribute to the mechanism of Pu colloid formation. At first, the fragmentation of initial PuO2 particles accelerates the overall process providing larger surface of contact between cavitation bubbles and solids. Furthermore, hydrogen formed during sonochemical water splitting enables reduction of Pu(IV) to more soluble Pu(III), which then reoxidizes yielding Pu(IV) colloid. Sonochemical colloid was compared with hydrolytic one using HRTEM, Pu LIII XAS, and STXM/NEXAFS (O K-edge) techniques. Both colloids are composed of quasi-spherical nanocrystalline particles of PuO2 (fcc, Fm¯3 m space group) measuring about 7 nm and 3 nm, respectively. Moreover, HRTEM revealed nanostructured morphology for initial PuO2. The EXAFS spectra of colloidal PuO2 nanoparticles were fitted using triple oxygen shell model for the first coordination sphere of Pu(IV). HRTEM and EXAFS studies revealed the correlation between the number of Pu-O and Pu-Pu contacts and atomic surface-to-volume ratio of studied PuO2 nanoparticles. The STXM/NEXAFS study indicated that the oxygen state of hydrolytic Pu colloid is influenced by hydrolyzed Pu(IV) species in much more extent than PuO2 nanoparticles of sonochemical colloid. In general, hydrolytic and sonochemical colloids can be described as core-shell nanoparticles composed of quasi stoichiometric PuO2 core and hydrolyzed Pu(IV) moieties at the surface shell.
Published: 2017
Full Text: View/download PDF

31. Structural characterization of Am(III) and Pu(III)-DOTA complexes

Author: Nicolas P. Martin, Thomas Dumas, Marie-Claire Illy, Yulia Moiseev, Laurence Berthon, Dominique Guillaumont, Matthieu Audras, Claude Berthon, Armand Bettelheim, Philippe Moisy, Yeshayahu Ben-Eliyahu, Israel Zilbermann, Sebastiano Cammelli, Christoph Hennig, CEA-Direction des Energies (ex-Direction de l'Energie Nucléaire) (CEA-DES (ex-DEN)), Commissariat à l'énergie atomique et aux énergies alternatives (CEA), Nuclear Research Center-Negev (NRCN), Ben-Gurion University of the Negev (BGU), Synchrotron SOLEIL (SSOLEIL), Centre National de la Recherche Scientifique (CNRS), and Helmholtz-Zentrum Dresden-Rossendorf (HZDR)
Subjects: Lanthanide, Coordination sphere, [PHYS.NUCL]Physics [physics]/Nuclear Theory [nucl-th], Inorganic chemistry, [PHYS.NEXP]Physics [physics]/Nuclear Experiment [nucl-ex], 010402 general chemistry, DFT calculations, 01 natural sciences, Inorganic Chemistry, chemistry.chemical_compound, Molecule, DOTA, UV-visible spectrophotometry, lanthanides, Carboxylate, Physical and Theoretical Chemistry, Ionic radius, Americium, 010405 organic chemistry, Ligand, Nuclear magnetic resonance spectroscopy, NMR, Plutonium, 0104 chemical sciences, Crystallography, EXAFS, chemistry
Abstract: International audience; The complexation of DOTA ligand (1,4,7,10-tetrazacyclodecane-1,4,7,10-tetraacetic acid) with two trivalent actinides (Am$^{3+}$ and Pu$^{3+}$) was investigated by UV-visible spectrophotometry, Nuclear Magnetic Resonance (NMR) spectroscopy and extended X-ray absorption fine structure (EXAFS) in conjunction with computational methods. The complexation process of these two cations is similar to what has been previously observed with lanthanides(III) of similar ionic radius. The complexation takes places in different steps and ends up with the formation of a (1:1) complex ((An(III)DOTA)(H2O)]$^-$ where the cation is bonded to the nitrogens of the ring, the four carboxylate arms and a water molecule is completing the coordination sphere. Nevertheless, the formation of An(III)-DOTA complexes is faster than the Ln(III)-DOTA systems of equivalent ionic radius. Furthermore, it is found that An-N distances are slightly shorter than Ln-N distances. Theoretical calculations have shown that the slightly higher affinity of DOTA toward Am over Nd is correlated with slightly enhanced Ligand-to-metal charge donation arising from oxygen and nitrogen atoms.
Published: 2017
Full Text: View/download PDF

32. Long-term behavior of refractory thorium-plutonium dioxide solid solutions

Author: Nicolas Dacheux, Philippe Moisy, Nassima Nadah, Gauthier Jouan, Laurent Claparede, Mireille Guigue, Interfaces de Matériaux en Evolution (LIME), Institut de Chimie Séparative de Marcoule (ICSM - UMR 5257), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Ecole Nationale Supérieure de Chimie de Montpellier (ENSCM)-Institut de Chimie du CNRS (INC)-Université de Montpellier (UM)-Centre National de la Recherche Scientifique (CNRS)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Ecole Nationale Supérieure de Chimie de Montpellier (ENSCM)-Institut de Chimie du CNRS (INC)-Université de Montpellier (UM)-Centre National de la Recherche Scientifique (CNRS), Département de recherche sur les procédés pour la mine et le recyclage du combustible (DMRC), CEA-Direction des Energies (ex-Direction de l'Energie Nucléaire) (CEA-DES (ex-DEN)), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA), and Centre National de la Recherche Scientifique (CNRS)-Institut de Chimie du CNRS (INC)-Université de Montpellier (UM)-Ecole Nationale Supérieure de Chimie de Montpellier (ENSCM)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Centre National de la Recherche Scientifique (CNRS)-Institut de Chimie du CNRS (INC)-Université de Montpellier (UM)-Ecole Nationale Supérieure de Chimie de Montpellier (ENSCM)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)
Subjects: Nuclear and High Energy Physics, Materials science, Inorganic chemistry, Oxide, Thorium, chemistry.chemical_element, 02 engineering and technology, 010402 general chemistry, 021001 nanoscience & nanotechnology, 01 natural sciences, 0104 chemical sciences, Plutonium, chemistry.chemical_compound, Nuclear Energy and Engineering, chemistry, Nitric acid, General Materials Science, Leaching (metallurgy), Crystallite, 0210 nano-technology, Dissolution, [CHIM.RADIO]Chemical Sciences/Radiochemistry, ComputingMilieux_MISCELLANEOUS, Solid solution
Abstract: The long-term behavior of Th0.87Pu0.13O2 was examined in nitric acid concentrations. The normalized dissolution rates after 3380 days, range from (1.4 ± 0.2) × 10−6 g m−2 d−1 in 5 M HNO3 down to (3.2 ± 0.4) × 10−8 g m−2 d−1 in 10−3 M HNO3, which confirms the high chemical durability of this solid solution. The amounts of plutonium measured in solution lead to 0.9% and 2.1% of dissolved solid in 1 M and 5 M HNO3, respectively. In such conditions, the time required to reach the full dissolution of the material varies from 430 years (5 M HNO3) to 18,000 years (10−3 M HNO3). Moreover, the partial order related to the proton activity (n = 0.45 ± 0.03) suggests that the dissolution is mainly driven by surface reactions occurring at the solid/liquid interface. The characterization of the leached samples by SEM shows small microstructural modifications (i.e. detachment of crystallites) and the absence of neoformed phase while from PXRD, the unit cell parameter and crystallite size are not significantly affected.
Published: 2017
Full Text: View/download PDF

33. Paramagnetism of Aqueous Actinide Cations. Part II: Theoretical Aspects and New Measurements on An(IV)

Author: Hélène Bolvin, Philippe Moisy, Dominique Guillaumont, Matthieu Autillo, Claude Berthon, Laetitia Guerin, Département RadioChimie et Procédés (DRCP), CEA-Direction des Energies (ex-Direction de l'Energie Nucléaire) (CEA-DES (ex-DEN)), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA), Systèmes étendus et magnétisme (LCPQ) (SEM), Laboratoire de Chimie et Physique Quantiques (LCPQ), Institut de Recherche sur les Systèmes Atomiques et Moléculaires Complexes (IRSAMC), Université Toulouse III - Paul Sabatier (UT3), Université de Toulouse (UT)-Université de Toulouse (UT)-Centre National de la Recherche Scientifique (CNRS)-Université Toulouse III - Paul Sabatier (UT3), Université de Toulouse (UT)-Université de Toulouse (UT)-Centre National de la Recherche Scientifique (CNRS)-Institut de Chimie du CNRS (INC)-Institut de Recherche sur les Systèmes Atomiques et Moléculaires Complexes (IRSAMC), Université de Toulouse (UT)-Université de Toulouse (UT)-Centre National de la Recherche Scientifique (CNRS)-Institut de Chimie du CNRS (INC), Institut National des Sciences Appliquées - Toulouse (INSA Toulouse), Institut National des Sciences Appliquées (INSA)-Institut National des Sciences Appliquées (INSA)-Centre National de la Recherche Scientifique (CNRS)-Université Toulouse III - Paul Sabatier (UT3), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Institut National des Sciences Appliquées - Toulouse (INSA Toulouse), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Institut de Chimie du CNRS (INC)-Institut de Recherche sur les Systèmes Atomiques et Moléculaires Complexes (IRSAMC), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Institut de Chimie du CNRS (INC), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS)-Université Toulouse III - Paul Sabatier (UT3), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS)-Institut de Chimie du CNRS (INC)-Institut de Recherche sur les Systèmes Atomiques et Moléculaires Complexes (IRSAMC), and Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS)-Institut de Chimie du CNRS (INC)
Subjects: Ligand field theory, 010405 organic chemistry, Chemistry, Inorganic chemistry, Solvation, 010402 general chemistry, 01 natural sciences, Magnetic susceptibility, Spectral line, 0104 chemical sciences, Ion, Inorganic Chemistry, [CHIM.THEO]Chemical Sciences/Theoretical and/or physical chemistry, Paramagnetism, Physical chemistry, Condensed Matter::Strongly Correlated Electrons, Curie constant, Complete active space, Physical and Theoretical Chemistry, ComputingMilieux_MISCELLANEOUS
Abstract: The magnetic properties of actinide(IV) (An(IV)) cations are investigated in various solutions (HClO4, HCl, and HNO3) by the Evans NMR method. The magnetic susceptibilities measured in noncomplexing medium are compared with the previous studies, and the influence of the medium is verified with new measurements in complexing solutions. To rationalize these results, spin–orbit complete active space perturbation theory at second order calculations are performed on the free ions and on the aquo complexes to determine the nature of electronic states, the magnetic susceptibility, and the UV–visible–near-IR spectra. The different factors contributing to the An(IV) magnetic properties were identified. The ligand field effect on the magnetic behavior (Curie constant and temperature-independent susceptibilities) was analyzed by considering different solvation environments. These results indicate a significant effect of the zero-field splitting of the ground J manifold on the An(IV) magnetic susceptibility.
Published: 2016
Full Text: View/download PDF

34. Magnetic susceptibility of actinide(III) cations: an experimental and theoretical study

Author: Hélène Bolvin, Matthieu Autillo, Claude Berthon, Philippe Moisy, Laetitia Guerin, Département RadioChimie et Procédés (DRCP), CEA-Direction des Energies (ex-Direction de l'Energie Nucléaire) (CEA-DES (ex-DEN)), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA), Systèmes étendus et magnétisme (LCPQ) (SEM), Laboratoire de Chimie et Physique Quantiques (LCPQ), Institut de Recherche sur les Systèmes Atomiques et Moléculaires Complexes (IRSAMC), Université Toulouse III - Paul Sabatier (UT3), Université de Toulouse (UT)-Université de Toulouse (UT)-Centre National de la Recherche Scientifique (CNRS)-Université Toulouse III - Paul Sabatier (UT3), Université de Toulouse (UT)-Université de Toulouse (UT)-Centre National de la Recherche Scientifique (CNRS)-Institut de Chimie du CNRS (INC)-Institut de Recherche sur les Systèmes Atomiques et Moléculaires Complexes (IRSAMC), Université de Toulouse (UT)-Université de Toulouse (UT)-Centre National de la Recherche Scientifique (CNRS)-Institut de Chimie du CNRS (INC), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS)-Université Toulouse III - Paul Sabatier (UT3), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS)-Institut de Chimie du CNRS (INC)-Institut de Recherche sur les Systèmes Atomiques et Moléculaires Complexes (IRSAMC), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS)-Institut de Chimie du CNRS (INC), Institut National des Sciences Appliquées - Toulouse (INSA Toulouse), Institut National des Sciences Appliquées (INSA)-Institut National des Sciences Appliquées (INSA)-Université Toulouse III - Paul Sabatier (UT3), and Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS)-Institut National des Sciences Appliquées - Toulouse (INSA Toulouse)
Subjects: Ligand field theory, Isotopes of uranium, 010405 organic chemistry, Radiochemistry, Analytical chemistry, General Physics and Astronomy, chemistry.chemical_element, Americium, Actinide, equipment and supplies, 010402 general chemistry, 01 natural sciences, 7. Clean energy, Magnetic susceptibility, 0104 chemical sciences, [CHIM.THEO]Chemical Sciences/Theoretical and/or physical chemistry, Curie's law, chemistry, 13. Climate action, Curie constant, Physical and Theoretical Chemistry, Radioactive decay, ComputingMilieux_MISCELLANEOUS
Abstract: In a previous paper, the influence of radioactive decay (α and β(-)) on magnetic susceptibility measurements by the Evans method has been demonstrated by the study of two americium isotopes. To characterize more accurately this phenomenon and particularly its influence on the Curie law, a new study has been performed on two uranium isotopes ((238)U and (233)U) and on tritiated water ((3)H2O). The results on the influence of α emissions have established a relationship between changes in the temperature dependence and the radioactivity in solution. Regarding the β(-) emissions, less influence was observed while no temperature dependence linked to this kind of radioactive emission could be identified. Once magnetic susceptibility measurements of actinide(iii) cations were corrected from radioactivity effects, methods of quantum chemistry have been used on free ions and aquo complexes to calculate the electronic structure explaining the magnetic properties of Pu(iii), Am(iii) and Cm(iii). The ligand field effect on the magnetic behavior (the Curie constant and temperature-independent susceptibilities) was analyzed by considering different solvation environments.
Published: 2016
Full Text: View/download PDF

35. Effect of ultrasonic frequency on H2O2 sonochemical formation rate in aqueous nitric acid solutions in the presence of oxygen

Author: Philippe Moisy, Sergey I. Nikitenko, Elodie Dalodière, Matthieu Virot, Sonochimie dans les Fluides Complexes (LSFC), Institut de Chimie Séparative de Marcoule (ICSM - UMR 5257), Centre National de la Recherche Scientifique (CNRS)-Institut de Chimie du CNRS (INC)-Université de Montpellier (UM)-Ecole Nationale Supérieure de Chimie de Montpellier (ENSCM)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Centre National de la Recherche Scientifique (CNRS)-Institut de Chimie du CNRS (INC)-Université de Montpellier (UM)-Ecole Nationale Supérieure de Chimie de Montpellier (ENSCM)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA), Département de recherche sur les procédés pour la mine et le recyclage du combustible (DMRC), CEA-Direction des Energies (ex-Direction de l'Energie Nucléaire) (CEA-DES (ex-DEN)), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA), and Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Ecole Nationale Supérieure de Chimie de Montpellier (ENSCM)-Institut de Chimie du CNRS (INC)-Université de Montpellier (UM)-Centre National de la Recherche Scientifique (CNRS)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Ecole Nationale Supérieure de Chimie de Montpellier (ENSCM)-Institut de Chimie du CNRS (INC)-Université de Montpellier (UM)-Centre National de la Recherche Scientifique (CNRS)
Subjects: Acoustics and Ultrasonics, Sonication, Analytical chemistry, chemistry.chemical_element, Nanotechnology, 02 engineering and technology, 010402 general chemistry, 01 natural sciences, Oxygen, Sonochemistry, Inorganic Chemistry, chemistry.chemical_compound, Nitric acid, Chemical Engineering (miscellaneous), Environmental Chemistry, Radiology, Nuclear Medicine and imaging, Hydrogen peroxide, NOx, ComputingMilieux_MISCELLANEOUS, Nitrous acid, Aqueous solution, Organic Chemistry, [CHIM.MATE]Chemical Sciences/Material chemistry, 021001 nanoscience & nanotechnology, 0104 chemical sciences, chemistry, 13. Climate action, 0210 nano-technology
Abstract: The influence of the ultrasonic frequency (20 kHz, 207 kHz, and 615 kHz) towards the formation kinetics of H2O2 under Ar and Ar/(20 vol.%)O2 atmospheres was evaluated in pure water and aqueous nitric solutions. Results obtained at low frequency ultrasound demonstrate that hydrogen peroxide formation is enhanced under an Ar/O2 gas mixture whatever the sonicated medium. Nevertheless, H2O2 yields are higher in aqueous nitric solutions whatever the nature of the saturating gas. These observations are consistent at high frequency ultrasound under Ar gas notwithstanding higher yields for H2O2. Surprisingly, an inverse tendency is observed for high frequency sonolysis carried out under an Ar/O2 atmosphere: higher yields of H2O2 are measured in pure water. Further studies in the presence of pure Ar revealed a more important decomposition of nitric acid under high frequency ultrasound leading to higher yields of both HNO2 in the liquid phase and NO in the gas phase. In the presence of Ar/O2 mixture, the intrabubble oxidation of NO causes cavitation bubble depletion in O2 leading to the drop of H2O2 yield. On the other hand, it was found that for Ar/(20 vol.%)O2 mixture there is no influence of oxygen on HNO2 yield whatever the ultrasonic frequency; this is most likely explained by two processes: (i) HNO2 formation results from nitrate-ion thermolysis in the liquid reaction zone surrounding the cavitation bubble, and (ii) effective intrabubble oxidation of NOx species by oxygen to nitrate-ion.
Published: 2016
Full Text: View/download PDF

36. The nature of chemical bonding in actinide and lanthanide ferrocyanides determined by X-ray absorption spectroscopy and density functional theory

Author: David K. Shuh, Clara Fillaux, Andreas C. Scheinost, Dominique Guillaumont, Thomas Dumas, Christophe Den Auwer, Philippe Moisy, Tolek Tyliszczak, and Sébastien Petit
Subjects: Lanthanide, X-ray absorption spectroscopy, Absorption spectroscopy, 010405 organic chemistry, Chemistry, General Physics and Astronomy, Electronic structure, 010402 general chemistry, 01 natural sciences, DFT, XANES, 0104 chemical sciences, Atomic orbital, Chemical bond, Physical chemistry, Reactivity (chemistry), Density functional theory, Physical and Theoretical Chemistry
Abstract: © the Owner Societies 2016. The electronic properties of actinide cations are of fundamental interest to describe intramolecular interactions and chemical bonding in the context of nuclear waste reprocessing or direct storage. The 5f and 6d orbitals are the first partially or totally vacant states in these elements, and the nature of the actinide ligand bonds is related to their ability to overlap with ligand orbitals. Because of its chemical and orbital selectivities, X-ray absorption spectroscopy (XAS) is an effective probe of actinide species frontier orbitals and for understanding actinide cation reactivity toward chelating ligands. The soft X-ray probes of the light elements provide better resolution than actinide L3-edges to obtain electronic information from the ligand. Thus coupling simulations to experimental soft X-ray spectral measurements and complementary quantum chemical calculations yields quantitative information on chemical bonding. In this study, soft X-ray XAS at the K-edges of C and N, and the L2,3-edges of Fe was used to investigate the electronic structures of the well-known ferrocyanide complexes K4FeII(CN)6, thorium hexacyanoferrate ThIVFeII(CN)6, and neodymium hexacyanoferrate KNdIIIFeII(CN)6. The soft X-ray spectra were simulated based on quantum chemical calculations. Our results highlight the orbital overlapping effects and atomic effective charges in the FeII(CN)6building block. In addition to providing a detailed description of the electronic structure of the ferrocyanide complex (K4FeII(CN)6), the results strongly contribute to confirming the actinide 5f and 6d orbital oddity in comparison to lanthanide 4f and 5d.
Published: 2016
Full Text: View/download PDF

37. Density and activity of pertechnetic acid aqueous solutions at T = 298.15 K

Author: Jean-François Dufrêche, Christian Sorel, Alexandre Ruas, L. Abiad, Manuel Miguirditchian, Philippe Moisy, P. Moeyaert, Département de recherche sur les procédés pour la mine et le recyclage du combustible (DMRC), CEA-Direction des Energies (ex-Direction de l'Energie Nucléaire) (CEA-DES (ex-DEN)), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA), Modélisation Mésoscopique et Chimie Théorique (LMCT), Institut de Chimie Séparative de Marcoule (ICSM - UMR 5257), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Ecole Nationale Supérieure de Chimie de Montpellier (ENSCM)-Institut de Chimie du CNRS (INC)-Université de Montpellier (UM)-Centre National de la Recherche Scientifique (CNRS)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Ecole Nationale Supérieure de Chimie de Montpellier (ENSCM)-Institut de Chimie du CNRS (INC)-Université de Montpellier (UM)-Centre National de la Recherche Scientifique (CNRS), and Centre National de la Recherche Scientifique (CNRS)-Institut de Chimie du CNRS (INC)-Université de Montpellier (UM)-Ecole Nationale Supérieure de Chimie de Montpellier (ENSCM)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Centre National de la Recherche Scientifique (CNRS)-Institut de Chimie du CNRS (INC)-Université de Montpellier (UM)-Ecole Nationale Supérieure de Chimie de Montpellier (ENSCM)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)
Subjects: Activity coefficient, Water activity, Thermodynamics, Pertechnetic acid, 02 engineering and technology, Electrolyte, 010402 general chemistry, 01 natural sciences, Perrhenic acid, chemistry.chemical_compound, 020401 chemical engineering, Binary data, General Materials Science, Osmotic coefficient, 0204 chemical engineering, Physical and Theoretical Chemistry, Molality, Aqueous solution, 6. Clean water, Atomic and Molecular Physics, and Optics, 0104 chemical sciences, [CHIM.THEO]Chemical Sciences/Theoretical and/or physical chemistry, chemistry
Abstract: Published isopiestic molalities for aqueous HReO4 solutions at T = 298.15 K are completed. Binary data (variation of the osmotic coefficient and activity coefficient of the electrolyte in solution in the water) at T = 298.15 K for perrhenic acid HReO4 are determined by direct water activity and osmolality measurements. The variation of the osmotic coefficient of this acid in water is represented mathematically according to a model recommended by the National Institute of Standards and Technology and according to the specific interaction theory. The data are also used to evaluate the parameters of the standard three-parameters of Pitzer’s ion-interaction model, along with the parameters of Archer’s four-parameter extended ion-interaction model, to higher molalities than previously advised. Experimental thermodynamic data are well represented by these models. Density variations at T = 298.15 K are also established and used to express the activity coefficient values on both the molar and molal concentration scales.
Published: 2015
Full Text: View/download PDF

38. On the stoichiometry and stability of americium(III) complexes with a hydrophilic SO3–Ph–BTP ligand, studied by liquid–liquid extraction

Author: Magdalena Rejnis, Philippe Moisy, Marie-Christine Charbonnel, Jerzy Narbutt, Łukasz Steczek, CEA-Direction des Energies (ex-Direction de l'Energie Nucléaire) (CEA-DES (ex-DEN)), Commissariat à l'énergie atomique et aux énergies alternatives (CEA), and Laboratoire de Chimie des Actinides (LCA)
Subjects: Solvent extraction, Curium, [PHYS.NUCL]Physics [physics]/Nuclear Theory [nucl-th], Health, Toxicology and Mutagenesis, Inorganic chemistry, chemistry.chemical_element, Americium, [PHYS.NEXP]Physics [physics]/Nuclear Experiment [nucl-ex], Article, Analytical Chemistry, Inorganic Chemistry, americium, Complexes, Liquid–liquid extraction, Phase (matter), Radiology, Nuclear Medicine and imaging, Americium(III), Spectroscopy, Aqueous solution, Chemistry, Ligand, Public Health, Environmental and Occupational Health, Pollution, Nuclear Energy and Engineering, Stoichiometry, Partitioning, Hydrophilic BTP ligand
Abstract: 1:1 and 1:2 complexes of americium(III) with a hydrophilic anionic SO3–Ph–BTP4− ligand were detected in acidic aqueous nitrate solutions by a solvent extraction method. The determined conditional stability constants of these complexes, logβ 1 = 4.35 ± 0.07 and logβ 2 = 7.67 ± 0.06, related to 1 M aqueous solutions, are much lower than the literature values for the analogous curium species, determined by TRLFS in very dilute aqueous solutions. There is also no evidence for the existence of the 1:3 Am3+ complex similar to the reported curium(III) complex. A hypothesis has been formulated to explain these discrepancies. It suggests the necessity to carefully check the equilibria in each phase of solvent extraction systems containing two competing ligands—lipophilic and hydrophilic.
Published: 2015
Full Text: View/download PDF

39. Determination of formation constants of uranyl(VI) complexes with a hydrophilic SO3-Ph-BTP ligand, using liquid-liquid extraction

Author: Jerzy Narbutt, Lukasz Steczek, Philippe Moisy, Marie-Christine Charbonnel, CEA-Direction des Energies (ex-Direction de l'Energie Nucléaire) (CEA-DES (ex-DEN)), and Commissariat à l'énergie atomique et aux énergies alternatives (CEA)
Subjects: Nuclear and High Energy Physics, Stripping (chemistry), [PHYS.NUCL]Physics [physics]/Nuclear Theory [nucl-th], Science, Inorganic chemistry, [PHYS.NEXP]Physics [physics]/Nuclear Experiment [nucl-ex], 010402 general chemistry, 01 natural sciences, uranyl ion, chemistry.chemical_compound, Liquid–liquid extraction, Safety, Risk, Reliability and Quality, Solvent extraction, Waste Management and Disposal, Instrumentation, complexes, 010405 organic chemistry, Ligand, stripping, formation constant, Condensed Matter Physics, Uranyl, solvent extraction, 0104 chemical sciences, hydrophilic poly-n-dentate ligands, Nuclear Energy and Engineering, chemistry, Stability constants of complexes
Abstract: Complex formation between uranyl ion, UO2 2+, and a hydrophilic anionic form of SO3-Ph-BTP4- ligand, L4-, in water was studied by liquid-liquid extraction experiments performed over a range of the ligand and HNO3 concentrations in the aqueous phase, at a constant concentration of nitrate anions at 25°C . The competition for UO2 2+ ions between the lipophilic TODGA extractant and the hydrophilic L4- ligand leads to the decrease in the uranyl distribution ratios, D, with an increasing L4- concentration. The model of the solvent extraction process used accounts - apart from uranyl complexation by TODGA and SO3-Ph-BTP4- - also for uranyl complexation by nitrates and for the decrease in the concentration of the free L4- ligand in the aqueous phase, due to its protonation, bonding in the uranyl complex and the distribution between the two liquid phases. The unusually strong dependence of the D values on the acidity, found in the experiment, could hardly be explained as due to L4- protonation merely. Three hypotheses were experimentally tested, striving to interpret the data in terms of additional extraction to the organic phase of ion associates of protonated TODGA cation with either partly protonated anionic L4- ligands or anionic UO2 2+ complexes with NO3 - or L4-. None of them has been confirmed. The analysis of the results, based on the formal correction of free ligand concentrations, points to the formation of 1 : 1 and 1 : 2 uranyl - SO3-Ph-BTP complexes in the aqueous phase. The conditional formation constant of the 1:1 complex has been determined, logßL,1 = 2.95 ± 0.15.
Published: 2015
Full Text: View/download PDF

40. Dissolution of Th1−xUxO2 : Effects of chemical composition and microstructure

Author: Nicolas Dacheux, Philippe Moisy, Florent Tocino, Nicolas Clavier, Laurent Claparede, Adel Mesbah, Stéphanie Szenknect, Interfaces de Matériaux en Evolution (LIME), Institut de Chimie Séparative de Marcoule (ICSM - UMR 5257), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Ecole Nationale Supérieure de Chimie de Montpellier (ENSCM)-Institut de Chimie du CNRS (INC)-Université de Montpellier (UM)-Centre National de la Recherche Scientifique (CNRS)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Ecole Nationale Supérieure de Chimie de Montpellier (ENSCM)-Institut de Chimie du CNRS (INC)-Université de Montpellier (UM)-Centre National de la Recherche Scientifique (CNRS), Laboratoire des Technologies des Traceurs (L2T), Commissariat à l'énergie atomique et aux énergies alternatives (CEA), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Ecole Nationale Supérieure de Chimie de Montpellier (ENSCM)-Institut de Chimie du CNRS (INC)-Université de Montpellier (UM)-Centre National de la Recherche Scientifique (CNRS), CEA/Marcoule, Centre National de la Recherche Scientifique (CNRS)-Institut de Chimie du CNRS (INC)-Université de Montpellier (UM)-Ecole Nationale Supérieure de Chimie de Montpellier (ENSCM)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Centre National de la Recherche Scientifique (CNRS)-Institut de Chimie du CNRS (INC)-Université de Montpellier (UM)-Ecole Nationale Supérieure de Chimie de Montpellier (ENSCM)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA), and Centre National de la Recherche Scientifique (CNRS)-Institut de Chimie du CNRS (INC)-Université de Montpellier (UM)-Ecole Nationale Supérieure de Chimie de Montpellier (ENSCM)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)
Subjects: Nuclear and High Energy Physics, Chemistry, Inorganic chemistry, chemistry.chemical_element, [CHIM.MATE]Chemical Sciences/Material chemistry, Uranium, [CHIM.INOR]Chemical Sciences/Inorganic chemistry, Uranyl, chemistry.chemical_compound, Nuclear Energy and Engineering, Nitric acid, [CHIM]Chemical Sciences, General Materials Science, Crystallite, Leaching (metallurgy), Chemical composition, Dissolution, [CHIM.RADIO]Chemical Sciences/Radiochemistry, ComputingMilieux_MISCELLANEOUS, Solid solution
Abstract: The dissolution of Th1−xUxO2 solid solutions was studied by varying independently several parameters such as chemical composition, leachate acidity, leaching temperature, firing temperature, and densification state. The chemical durability of the samples was significantly affected by the uranium mole loading probably due to the oxidation of tetravalent uranium into uranyl during the dissolution process. The influence of nitric acid concentration and temperature also showed that the behavior of Th1−xUxO2 solid solutions with higher uranium incorporation fractions (x = 0.52, 0.75 and 1) differed significantly from that of Th0.84U0.16O2. Strong modifications of the dissolution mechanism occurring at the solid/liquid interface for the higher uranium loadings could explain this difference. It could result in the existence of the fast oxidation of U(IV) to U(VI) at the solid/solution interface then of the detachment of activated complexes formed with U(VI). Furthermore, initial normalized dissolution rate slightly depended on the elimination of crystal defects for firing temperatures below 900 °C but was almost independent of the crystallite size (T ⩾ 900 °C). Finally, dissolution tests on sintered Th0.84U0.16O2 samples showed that RL(Th) values decreased by an order of magnitude when the relative density increased from 79% to 89%.
Published: 2015
Full Text: View/download PDF

41. Sonochemical redox reactions of Pu( iii ) and Pu( iv ) in aqueous nitric solutions

Author: Laurent Venault, Sergey I. Nikitenko, Matthieu Virot, Philippe Moisy, Sonochimie dans les Fluides Complexes (LSFC), Institut de Chimie Séparative de Marcoule (ICSM - UMR 5257), Centre National de la Recherche Scientifique (CNRS)-Institut de Chimie du CNRS (INC)-Université de Montpellier (UM)-Ecole Nationale Supérieure de Chimie de Montpellier (ENSCM)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Centre National de la Recherche Scientifique (CNRS)-Institut de Chimie du CNRS (INC)-Université de Montpellier (UM)-Ecole Nationale Supérieure de Chimie de Montpellier (ENSCM)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA), Département de recherche sur les procédés pour la mine et le recyclage du combustible (DMRC), CEA-Direction des Energies (ex-Direction de l'Energie Nucléaire) (CEA-DES (ex-DEN)), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA), and Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Ecole Nationale Supérieure de Chimie de Montpellier (ENSCM)-Institut de Chimie du CNRS (INC)-Université de Montpellier (UM)-Centre National de la Recherche Scientifique (CNRS)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Ecole Nationale Supérieure de Chimie de Montpellier (ENSCM)-Institut de Chimie du CNRS (INC)-Université de Montpellier (UM)-Centre National de la Recherche Scientifique (CNRS)
Subjects: Aqueous solution, Reducing agent, Chemistry, Inorganic chemistry, Redox, Sonochemistry, Inorganic Chemistry, Autocatalysis, chemistry.chemical_compound, Reagent, Sulfamic acid, Steady state (chemistry), [CHIM.RADIO]Chemical Sciences/Radiochemistry, Nuclear chemistry
Abstract: International audience; The behavior of Pu(IV) and Pu(III) was investigated in aqueous nitric solutions under ultrasound irradiation (Ar, 20 kHz). In the absence of anti-nitrous reagents, ultrasound has no effect on Pu(IV), while Pu(III) can be rapidly oxidized to Pu(IV) due to the autocatalytic formation of HNO$_2$ induced by HNO$_3$ sonolysis. In the presence of anti-nitrous reagents (sulfamic acid or hydrazinium nitrate), Pu(IV) can be sonochemically reduced to Pu(III). The reduction follows a first order reaction law and leads to a steady state where Pu(IV) and Pu(III) coexist in solution. The reduction process is attributed to the sonochemical generation of H$_2$O$_2$ in solution. The kinetics attributed to the reduction of Pu(IV) are however higher than those related to the formation of H$_2$O$_2$ which, after several hypotheses, is explained by the sonochemical erosion of the titanium-based sonotrode. Titanium particles thereby generated can be solubilized under ultrasound and generate Ti(III) as an intermediate species, a strong reducing agent able to react with Pu(IV).
Published: 2015
Full Text: View/download PDF

42. X-ray absorption spectroscopy investigations on radioactive matter using MARS beamline at SOLEIL synchrotron

Author: René Bes, Jean-Luc Béchade, Olivier Proux, Isabelle Llorens, Hervé Hermange, Denis Menut, Sami Safi, Bruno Sitaud, Pier Lorenzo Solari, Sebastiano Cammelli, Philippe Moisy, Carole Bresson, Jean-Louis Hazemann, Michel L. Schlegel, Sandrine Wahu, Philippe Martin, Guillaume Othmane, Christophe Den Auwer, Synchrotron SOLEIL (SSOLEIL), Centre National de la Recherche Scientifique (CNRS), CEA Cadarache, Commissariat à l'énergie atomique et aux énergies alternatives (CEA), Institut de minéralogie, de physique des matériaux et de cosmochimie (IMPMC), Université Pierre et Marie Curie - Paris 6 (UPMC)-Institut de recherche pour le développement [IRD] : UR206-Muséum national d'Histoire naturelle (MNHN)-Centre National de la Recherche Scientifique (CNRS), Institut de Physique Nucléaire d'Orsay (IPNO), Centre National de la Recherche Scientifique (CNRS)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Université Paris-Sud - Paris 11 (UP11), Laboratoire d'Etudes du Comportement à Long Terme des matériaux de conditionnement (LCLT), Département de recherche sur les technologies pour l'enrichissement, le démantèlement et les déchets (DE2D), CEA-Direction des Energies (ex-Direction de l'Energie Nucléaire) (CEA-DES (ex-DEN)), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-CEA-Direction des Energies (ex-Direction de l'Energie Nucléaire) (CEA-DES (ex-DEN)), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA), Matériaux, Rayonnements, Structure (MRS), Institut Néel (NEEL), Université Joseph Fourier - Grenoble 1 (UJF)-Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP )-Centre National de la Recherche Scientifique (CNRS)-Université Joseph Fourier - Grenoble 1 (UJF)-Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP )-Centre National de la Recherche Scientifique (CNRS), Institut de Chimie de Nice (ICN), Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS)-Université Côte d'Azur (UCA)-Université Nice Sophia Antipolis (... - 2019) (UNS), COMUE Université Côte d'Azur (2015-2019) (COMUE UCA)-COMUE Université Côte d'Azur (2015-2019) (COMUE UCA), Muséum national d'Histoire naturelle (MNHN)-Université Pierre et Marie Curie - Paris 6 (UPMC)-Institut de recherche pour le développement [IRD] : UR206-Centre National de la Recherche Scientifique (CNRS), Université Paris-Sud - Paris 11 (UP11)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Centre National de la Recherche Scientifique (CNRS), Département de recherche sur les Procédés et Matériaux pour les Environnements complexes (DPME), Matériaux, Rayonnements, Structure (NEEL - MRS), Université Nice Sophia Antipolis (1965 - 2019) (UNS), COMUE Université Côte d'Azur (2015-2019) (COMUE UCA)-COMUE Université Côte d'Azur (2015-2019) (COMUE UCA)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS)-Université Côte d'Azur (UCA), Université Joseph Fourier - Grenoble 1 (UJF)-Centre National de la Recherche Scientifique (CNRS)-Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP )-Université Joseph Fourier - Grenoble 1 (UJF)-Centre National de la Recherche Scientifique (CNRS)-Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP ), Université Nice Sophia Antipolis (... - 2019) (UNS), COMUE Université Côte d'Azur (2015 - 2019) (COMUE UCA)-COMUE Université Côte d'Azur (2015 - 2019) (COMUE UCA)-Université Côte d'Azur (UCA)-Centre National de la Recherche Scientifique (CNRS), Institut de recherche pour le développement [IRD] : UR206-Centre National de la Recherche Scientifique (CNRS)-Muséum national d'Histoire naturelle (MNHN)-Université Pierre et Marie Curie - Paris 6 (UPMC), CEA-Direction de l'Energie Nucléaire (CEA-DEN), Université Grenoble Alpes (UGA)-Centre National de la Recherche Scientifique (CNRS)-Université Joseph Fourier - Grenoble 1 (UJF), Centre National de la Recherche Scientifique (CNRS)-Université Nice Sophia Antipolis (... - 2019) (UNS), Université Côte d'Azur (UCA)-Université Côte d'Azur (UCA), Université Joseph Fourier - Grenoble 1 (UJF)-Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP )-Centre National de la Recherche Scientifique (CNRS), COMUE Université Côte d'Azur (2015 - 2019) (COMUE UCA)-COMUE Université Côte d'Azur (2015 - 2019) (COMUE UCA)-Centre National de la Recherche Scientifique (CNRS)-Université Côte d'Azur (UCA), and Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP )-Centre National de la Recherche Scientifique (CNRS)-Université Joseph Fourier - Grenoble 1 (UJF)-Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP )-Centre National de la Recherche Scientifique (CNRS)-Université Joseph Fourier - Grenoble 1 (UJF)
Subjects: Absorption spectroscopy, XAS, [PHYS.PHYS.PHYS-ACC-PH]Physics [physics]/Physics [physics]/Accelerator Physics [physics.acc-ph], Analytical chemistry, 02 engineering and technology, [PHYS.NEXP]Physics [physics]/Nuclear Experiment [nucl-ex], 010402 general chemistry, 01 natural sciences, law.invention, Synchrotron, Neptunium, law, X-rays, Physical and Theoretical Chemistry, Molybdenum, [PHYS]Physics [physics], X-ray absorption spectroscopy, Extended X-ray absorption fine structure, Chemistry, Radiochemistry, Thorium, Mars Exploration Program, 021001 nanoscience & nanotechnology, HERFD-XAS, XANES, 0104 chemical sciences, Beamline, Uranium, Zirconium, 0210 nano-technology, Powder diffraction
Abstract: The MARS beamline at the SOLEIL synchrotron is dedicated to the characterization of radioactive material samples. One great advantage of the beamline is the possibility to characterize about 380 radionuclides by different X-ray techniques in the same place. This facility is unique in Europe. A wide energy range from around 3.5 keV to 36 keV K-edges from K to Cs, and L3 edges from Cd to Am and beyond can be used. The MARS beamline is optimized for X-ray absorption spectroscopy techniques (XANES/EXAFS), powder diffraction (XRD) but x-ray fluorescence (XRF) analysis, High Energy Resolution Fluorescence Detected -XAS (HERFD-XAS), X-ray Emission (XES) and μ-XAS/XRD are also possible. A description of the beamline as well as its performances are given in a first part. Then some scientific examples of XAS studies from users are presented which cover a wide variety of topics in radiochemistry and nuclear materials.
Published: 2014
Full Text: View/download PDF

43. Paramagnetism of Aqueous Actinide Cations. Part I: Perchloric Acid Media

Author: Laetitia Guerin, Kenneth L. Nash, Steve Jan, Thomas F. Wall, Philippe Moisy, Claude Berthon, Claire Le Naour, Matthieu Autillo, Département RadioChimie et Procédés (DRCP), CEA-Direction des Energies (ex-Direction de l'Energie Nucléaire) (CEA-DES (ex-DEN)), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA), Institut de Physique Nucléaire d'Orsay (IPNO), and Université Paris-Sud - Paris 11 (UP11)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Centre National de la Recherche Scientifique (CNRS)
Subjects: Curie–Weiss law, 010405 organic chemistry, Magnetism, Inorganic chemistry, Actinide, 010402 general chemistry, 01 natural sciences, Magnetic susceptibility, 0104 chemical sciences, Inorganic Chemistry, Perchlorate, chemistry.chemical_compound, Paramagnetism, chemistry, Diamagnetism, Perchloric acid, [PHYS.PHYS.PHYS-CHEM-PH]Physics [physics]/Physics [physics]/Chemical Physics [physics.chem-ph], Physical and Theoretical Chemistry
Abstract: A comprehensive study of actinide cation paramagnetism in acidic aqueous solution has been completed in perchlorate media. Employing the Evans method, all the readily accessible actinide cations have been studied using our specially outfitted NMR spectrometer equipped for use with radioactive samples. The effective magnetic moments observed, ranging from 0 to 13 μB, differ from the isoelectronic lanthanides, previous solid actinide studies, and older solution studies. Actinide (IV) and (V) ions show less paramagnetic character, while some actinide (III) ions exhibit greater paramagnetic behavior than predicted from free-ion calculation. Temperature dependence of actinide magnetic susceptibilities from 5 to 80 °C are in good agreement with a Curie-like law except for U(VI), which appears to be temperature-independent. Diamagnetic behavior of Th(IV) exhibits a very low temperature dependence of the magnetic susceptibility. Some explanations for the observations are offered, and the 5f electron behavior is compared to the 4f analogues.
Published: 2014
Full Text: View/download PDF

44. Effect of hydration and thermal treatment on ceria surface using non-intrusive techniques

Author: Jérémy Gaillard, Sylvie Del Confetto, Michael Odorico, Rachel Calvet, Renaud Podor, Laurent Venault, Philippe Moisy, Jean-Luc Pellequer, Nicolas Vigier, Nicolas Clavier, Département RadioChimie et Procédés (DRCP), CEA-Direction des Energies (ex-Direction de l'Energie Nucléaire) (CEA-DES (ex-DEN)), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA), Centre de recherche d'Albi en génie des procédés des solides divisés, de l'énergie et de l'environnement (RAPSODEE), Centre National de la Recherche Scientifique (CNRS)-IMT École nationale supérieure des Mines d'Albi-Carmaux (IMT Mines Albi), Institut Mines-Télécom [Paris] (IMT)-Institut Mines-Télécom [Paris] (IMT), Interfaces de Matériaux en Evolution (LIME), Institut de Chimie Séparative de Marcoule (ICSM - UMR 5257), Centre National de la Recherche Scientifique (CNRS)-Institut de Chimie du CNRS (INC)-Université de Montpellier (UM)-Ecole Nationale Supérieure de Chimie de Montpellier (ENSCM)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Centre National de la Recherche Scientifique (CNRS)-Institut de Chimie du CNRS (INC)-Université de Montpellier (UM)-Ecole Nationale Supérieure de Chimie de Montpellier (ENSCM)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA), Etude de la Matière en Mode Environnemental (L2ME), Service de Biochimie et Toxicologie Nucléaire (SBTN), Commissariat à l'énergie atomique et aux énergies alternatives (CEA), Institut de biologie structurale (IBS - UMR 5075 ), Université Grenoble Alpes [2016-2019] (UGA [2016-2019])-Institut de Recherche Interdisciplinaire de Grenoble (IRIG), Direction de Recherche Fondamentale (CEA) (DRF (CEA)), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Direction de Recherche Fondamentale (CEA) (DRF (CEA)), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Centre National de la Recherche Scientifique (CNRS), AREVA, Groupe AREVA, Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Ecole Nationale Supérieure de Chimie de Montpellier (ENSCM)-Institut de Chimie du CNRS (INC)-Université de Montpellier (UM)-Centre National de la Recherche Scientifique (CNRS)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Ecole Nationale Supérieure de Chimie de Montpellier (ENSCM)-Institut de Chimie du CNRS (INC)-Université de Montpellier (UM)-Centre National de la Recherche Scientifique (CNRS), and Centre National de la Recherche Scientifique (CNRS)-Université Grenoble Alpes [2016-2019] (UGA [2016-2019])-Institut de Recherche Interdisciplinaire de Grenoble (IRIG)
Subjects: Nuclear and High Energy Physics, Inorganic chemistry, Oxide, Thermal treatment, law.invention, chemistry.chemical_compound, symbols.namesake, [SPI]Engineering Sciences [physics], Adsorption, Nuclear Energy and Engineering, chemistry, 13. Climate action, law, Inverse gas chromatography, symbols, Surface modification, Hydroxide, General Materials Science, Calcination, Raman spectroscopy
Abstract: International audience; The evolution of plutonium dioxide surface due to water adsorption seems to influence H-2 generation through the radiolysis of adsorbed water. Surface evolution of ceria, a non-radioactive surrogate for plutonium dioxide, was investigated using Inverse Gas Chromatography (IGC), Raman spectroscopy, Environmental Scanning Electronic Microscopy (ESEM) and Atomic Force Microscopy (AFM). IGC highlights the complexity of ceria surface revealing three different adsorption sites on surface and indicate a surface evolution upon hydration. Thermal treatment appears to regenerate at least partially the initial surface state before hydration. IGC points out the influence of calcination temperature of ceria precursor on surface reactivity. The nature of surface modification was investigated by Raman spectroscopy which suggests formation of superficial hydroxide layer. ESEM and AFM were used to study potential surface topology modification upon superficial layer formation. Cerium hydroxide forms as a superficial layer with a nanostructure differing from the one of the oxide.
Published: 2014
Full Text: View/download PDF

45. Uranium carbide dissolution in nitric solution: Sonication vs. silent conditions

Author: Tony Chave, Sergey I. Nikitenko, Philippe Moisy, Matthieu Virot, Stéphanie Szenknect, Nicolas Dacheux, Sonochimie dans les Fluides Complexes (LSFC), Institut de Chimie Séparative de Marcoule (ICSM - UMR 5257), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Ecole Nationale Supérieure de Chimie de Montpellier (ENSCM)-Institut de Chimie du CNRS (INC)-Université de Montpellier (UM)-Centre National de la Recherche Scientifique (CNRS)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Ecole Nationale Supérieure de Chimie de Montpellier (ENSCM)-Institut de Chimie du CNRS (INC)-Université de Montpellier (UM)-Centre National de la Recherche Scientifique (CNRS), Interfaces de Matériaux en Evolution (LIME), Département de recherche sur les procédés pour la mine et le recyclage du combustible (DMRC), CEA-Direction des Energies (ex-Direction de l'Energie Nucléaire) (CEA-DES (ex-DEN)), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA), and Centre National de la Recherche Scientifique (CNRS)-Institut de Chimie du CNRS (INC)-Université de Montpellier (UM)-Ecole Nationale Supérieure de Chimie de Montpellier (ENSCM)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Centre National de la Recherche Scientifique (CNRS)-Institut de Chimie du CNRS (INC)-Université de Montpellier (UM)-Ecole Nationale Supérieure de Chimie de Montpellier (ENSCM)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)
Subjects: Nuclear and High Energy Physics, Nitrous acid, Sonication, Induction period, Inorganic chemistry, Kinetics, 02 engineering and technology, [CHIM.MATE]Chemical Sciences/Material chemistry, equipment and supplies, 010402 general chemistry, 021001 nanoscience & nanotechnology, 01 natural sciences, 0104 chemical sciences, Sonochemistry, chemistry.chemical_compound, Nuclear Energy and Engineering, chemistry, Nitric acid, General Materials Science, Uranium carbide, 0210 nano-technology, Dissolution, ComputingMilieux_MISCELLANEOUS
Abstract: The dissolution of uranium carbide (UC) in nitric acid media is considered by means of power ultrasound (sonication) or magnetic stirring. The induction period required to initiate UC dissolution was found to be dramatically shortened when sonicating a 3 M nitric solution (Ar, 20 kHz, 18 W cm −2 , 20 °C). At higher acidity, magnetic stirring offers faster dissolution kinetics compared to sonication. Ultrasound-assisted UC dissolution is found to be passivated after ∼60% dissolution and remains incomplete whatever the acidity which is confirmed by ICP–AES, LECO and SEM–EDX analyses. In general, the kinetics of UC dissolution is linked to the in situ generation of nitrous acid in agreement with the general mechanism of UC dissolution; the nitrous acid formation is reported to be faster under ultrasound at low acidity due to the nitric acid sonolysis. The carbon balance shared between the gaseous, liquid, and solid phases is strongly influenced by the applied dissolution procedure and HNO 3 concentration.
Published: 2013
Full Text: View/download PDF

46. Absence of 232,230,228 Th enhancement decay by ultrasound exposure

Author: Virginie Cousin, Rachel Pflieger, Sergey I. Nikitenko, Jean Aupiais, Philippe Moisy, DAM Île-de-France (DAM/DIF), Direction des Applications Militaires (DAM), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA), CEA-Direction des Energies (ex-Direction de l'Energie Nucléaire) (CEA-DES (ex-DEN)), Commissariat à l'énergie atomique et aux énergies alternatives (CEA), and Département RadioChimie et Procédés (DRCP)
Subjects: Thesaurus (information retrieval), Information retrieval, Chemistry, business.industry, Ultrasound, Ultrasound exposure, 02 engineering and technology, 021001 nanoscience & nanotechnology, 01 natural sciences, 010305 fluids & plasmas, 0103 physical sciences, [CHIM]Chemical Sciences, Physical and Theoretical Chemistry, 0210 nano-technology, business, [CHIM.RADIO]Chemical Sciences/Radiochemistry, ComputingMilieux_MISCELLANEOUS
Abstract: We report on our attempt to reproduce the 228Th decay enhancement under the effect of power ultrasound claimed recently in the literature. The evolution of natural thorium isotopic composition (232Th, 230Th, and 228Th) in various aqueous solutions submitted to 20 kHz power ultrasound (0.18 W mL−1, 20 ºC, Ar). The radioactivities of the three isotopes of thorium (232Th, 230Th and 228Th) were followed by α liquid scintillation counting technique. No change was detected during ultrasonic irradiation. Our results demonstrate that under the studied conditions the rate of Th isotopes radioactive decay is not modified under the effect of ultrasound on aqueous solutions of thorium salts.
Published: 2013
Full Text: View/download PDF

47. Speciation in aqueous solutions of nitric acid

Author: S. P. Hlushak, S. Jan, Alexandre Ruas, Jean-Pierre Simonin, Olivier Bernard, Philippe Moisy, S. De Sio, Patrick Pochon, PHysicochimie des Electrolytes et Nanosystèmes InterfaciauX (PHENIX), Université Pierre et Marie Curie - Paris 6 (UPMC)-Ecole Superieure de Physique et de Chimie Industrielles de la Ville de Paris (ESPCI Paris), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Centre National de la Recherche Scientifique (CNRS)-Institut de Chimie du CNRS (INC), and Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS)
Subjects: Inorganic chemistry, Analytical chemistry, 02 engineering and technology, Spectrum Analysis, Raman, 010402 general chemistry, Nitric Acid, 01 natural sciences, Ion, Inorganic Chemistry, chemistry.chemical_compound, symbols.namesake, Nitrate, Nitric acid, Genetic algorithm, Molecule, [CHIM]Chemical Sciences, Osmotic coefficient, Aqueous solution, Water, 021001 nanoscience & nanotechnology, 0104 chemical sciences, Solutions, chemistry, symbols, 0210 nano-technology, Raman spectroscopy
Abstract: International audience; In this study, speciation in aqueous solutions of nitric acid at 25 degrees C was assessed in two independent ways. First, Raman experiments were carried out and interpreted in terms of free nitrate ions, ion pairs and neutral HNO3 molecules. In parallel, a model was developed to account for the formation of these two kinds of pairs. It was based on an extension of the binding mean spherical approximation (BiMSA), or associative MSA (AMSA), in which the size and the charge of the ions in the chemical pair may differ from those of the free ions. A simultaneous fit of the osmotic coefficient and of the proportion of free ions (obtained from Raman spectroscopy experiments) led to an estimation of the speciation in nitric acid solutions. The result obtained using this procedure was compared with the estimation obtained from the Raman experiments.
Published: 2013
Full Text: View/download PDF

48. Specific Interaction between Uranium Anionic Complexes and the Cations of Bis(trifluoromethylsulfonyl)imide Based Ionic Liquids

Author: Philippe Guilbaud, Claire Le Naour, Philippe Moisy, Céline Cannes, Institut de Physique Nucléaire d'Orsay (IPNO), Université Paris-Sud - Paris 11 (UP11)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Centre National de la Recherche Scientifique (CNRS), Département RadioChimie et Procédés (DRCP), CEA-Direction des Energies (ex-Direction de l'Energie Nucléaire) (CEA-DES (ex-DEN)), and Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)
Subjects: Valence (chemistry), Chemistry, Inorganic chemistry, chemistry.chemical_element, 02 engineering and technology, Uranium, 010402 general chemistry, 021001 nanoscience & nanotechnology, 01 natural sciences, Concentration ratio, Chemical reaction, Redox, 0104 chemical sciences, Inorganic Chemistry, chemistry.chemical_compound, Ionic liquid, Electrode, [PHYS.PHYS.PHYS-CHEM-PH]Physics [physics]/Physics [physics]/Chemical Physics [physics.chem-ph], Physical and Theoretical Chemistry, 0210 nano-technology, Imide
Abstract: The redox properties of uranium(IV) hexachloro complex have been investigated with a glassy carbon electrode in four bis(trifluoromethylsulfonyl)imide (Tf2N(-)) based ionic liquids (ILs): the 1-butyl-3-methylimidazolium ([BuMeIm](+)), the 1-butyl-2,3-dimethylimidazolium ([BuMe2Im](+)), the N-butylmethylpyrrolidinium ([BuMePyr](+)), and the tributyl-methylammonium ([MeBu3N](+)). The cyclic voltammetric analysis has revealed two main redox systems: U(V)Cl6(-)/U(IV)Cl6(2-) around 0.2 V and U(IV)Cl6(2-)/U(III)Cl6(3-) around -2 V. The formation of U(V)Cl6(-), a non-dioxo uranium(V) species, can then be observed at the electrode in [Tf2N](-) based ILs. This work also provides evidence of a specific interaction between the uranium anionic species and the IL cations because the standard potentials of both redox couples depend on the IL. The interaction extent has been evaluated by comparison of the IL cation number associated with the uranium anionic complex. For that purpose, the standard potentials of both systems have been measured in the less interacting medium [MeBu3N][Tf2N] as a function of the [BuMeIm](+), [BuMe2Im](+), and [BuMePyr](+) concentration. Predominance diagrams for uranium hexachloro complexes, analogous to the Pourbaix diagram, have then been built in [MeBu3N][Tf2N] depending on the IL cations concentration. The exploitation of these diagrams leads to the conclusion that the interaction is function of the charge of the uranium hexachloro complex (U(V)Cl6(-)U(IV)Cl6(2-)U(III)Cl6(3-)) and the IL cation ([BuMe2Im](+)[BuMePyr](+)[BuMeIm](+)). The influence of the IL cation could be correlated to the size and the electropositivity of the IL cation. The association would occur by H-bonding and electrostatic interaction. Ab initio calculations were also carried out to evaluate the strength of the interaction between the anionic uranium(IV) chloro complex and the IL cations. The results show that [BuMeIm](+) interacts the most and [MeBu3N](+) the least with U(IV)Cl6(2-), and the magnitude of the interaction is comparable for [BuMe2Im](+) and [BuMePyr](+).
Published: 2013
Full Text: View/download PDF

49. Short note on the hydrolysis and complexation of neptunium(IV) in HEPES solution

Author: Gilles Subra, S. Dahou, C. Vidaud, Sébastien Petit, Christophe Den Auwer, Christoph Hennig, Andreas C. Scheinost, and Philippe Moisy
Subjects: Neptunium, EXAFS, Chemistry, HEPAS, Physical and Theoretical Chemistry, Humanities, Nuclear chemistry
Abstract: The speciation of actinides in environmental or biological media is often difficult to assess because it involves complex media. We would like to report here on the properties of Np(IV) cation in the well known biological HEPES (4-(2-hydroxyethyl)-1-piperazineethanesulfonic acid) buffer medium. HEPES has been targeted because the possibility to use this biological buffer in actinide toxicological studies presents several advantages although the possible effects of concentrated HEPES medium on the hydrolysis of the actinides (in particular at oxidation state +IV) has not been studied yet. A combination of spectrophotometric and EXAFS measurements at the Np L III edge shows that stable hydrolyzed neptunium(IV) clusters are obtained between pH 2.5 and 4. In a second step, in order to better understand the reactivity of these hydrolysis species formed in HEPES, the effect of a strong chelating ligands such as the hydroxamic acid (HA) or desferrioxamine (DFO) siderophores has been also investigated using spectrophotometry and EXAFS. Upon addition of HA or DFO, the hydrolyzed clusters of Np(IV) are unstable and monomeric complexes are formed and yield Np environments that are very similar to that of crystallized Pu-DFOE complex [Al(H2O)6][Pu(DFE)(H2O)3]2(CF3SO3)5·10H2O reported in the literature.
Published: 2013

50. Determination of the Bromley contributions to estimate the activity coefficient of neodymium electrolytes

Author: Philippe Moisy, Murielle Bertrand, Edouard Plasari, S. Lalleman, Christian Sorel, Département de recherche sur les procédés pour la mine et le recyclage du combustible (DMRC), CEA-Direction des Energies (ex-Direction de l'Energie Nucléaire) (CEA-DES (ex-DEN)), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA), Laboratoire Réactions et Génie des Procédés (LRGP), Université de Lorraine (UL)-Centre National de la Recherche Scientifique (CNRS), Service de Chimie des Procédés de Séparation (SCPS), and Commissariat à l'énergie atomique et aux énergies alternatives (CEA)
Subjects: Activity coefficient, Work (thermodynamics), REPRESENTATION, Activity coefficients, General Chemical Engineering, Thermodynamics, chemistry.chemical_element, 02 engineering and technology, Precipitation, Bromley equation, 010402 general chemistry, 7. Clean energy, 01 natural sciences, Neodymium, Industrial and Manufacturing Engineering, 020401 chemical engineering, ISOPIESTIC DETERMINATION, AQUEOUS-SOLUTIONS, WATER, [SPI.GPROC]Engineering Sciences [physics]/Chemical and Process Engineering, CALCIUM-SULFATE, 0204 chemical engineering, Chemistry, Applied Mathematics, General Chemistry, Actinide, BINARY, Spent nuclear fuel, 0104 chemical sciences, Solutions, NITRIC-ACID, Specific ion interaction theory, MOLECULAR-DYNAMICS, THERMODYNAMIC PROPERTIES, Ternary operation, Simulation, MEAN SPHERICAL APPROXIMATION
Abstract: International audience; In the spent nuclear fuel reprocessing, solutions of actinides and lanthanides are concentrated and cannot be assumed as ideal ones. Activity coefficients have then to be calculated to take into account the deviation from ideality. The aim of this study is to determine new neodymium individual contributions for the calculation of activity coefficients using the Bromley method. A comparison with experimental data demonstrates that, with the contribution values of this work, the Bromley method can be successfully applied in ternary mixtures for the calculation of activity coefficients of neodymium compounds in aqueous solutions for ionic strengths up to 6 mol kg(-1) as claimed by Bromley. The simple method described in this paper can be used to correct or to determine the contributions of any other ion.
Published: 2012
Full Text: View/download PDF

Catalog

Books, media, physical & digital resources

See catalog results

Searchworks

Select search scope, currently: Articles Catalog books, media & more in Jio Institute collections Articles journal articles & other e-resources

Search

Search Constraints

Refine your results

Search Limiters

Topic

Publication Year Range

Publication Type

Journal

Database

Publisher

78 results on '"Philippe, Moisy"'

Search Results

Catalog

Select search scope, currently: Articles

Catalog

books, media & more in Jio Institute collections

Articles

journal articles & other e-resources