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International audience; The solid waste of olive oil extraction processes (olive pomace (OP)) was converted into activated carbon (AC) through merely treating it with NaOH and then encapsulating it within sodium alginate (SA) in beads by crosslinking (SA-AC beads). The prepared SA-AC beads were utilized as an adsorbent for the elimination and recovery of phenolic compounds (PCs) from olive mill wastewater (OMWW) following a zero liquid and waste discharge approach to implement and promote the circular economy concept. The novel AC and SA-AC beads were characterized by scanning electron microscopy (SEM), energy-dispersive X-ray spectroscopy (EDS), Fourier transform infrared spectroscopy (FTIR) and Brunauer, Emmett and Teller (BET) analysis. The adsorption performance of these beads was evaluated in batch and fixedbed reactors operated in a concurrent flow system. The results revealed that an adsorption capacity of 68 mg g-1 was attained for 4,000 mg L-1 phenolic compounds. The kinetics of the adsorption process of the PCs fit a pseudo second-order model, and the most likely mechanism took place in two stages. The adsorption isotherm conformed to the Langmuir model, representing the monolayer adsorption of the phenolic compounds. The dynamic models were used, and they accurately represented the breakthrough curves. Considering PC recovery and process reusability, a regeneration experiment of SA-AC beads was carried out in fixed-bed reactors. SA-AC beads showed a high percentage desorption > 40% using ethanol and were efficient after several cycles of OMWW treatment and phenol recovery.

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Membrane contactors offer promising performances for the intensification of gas liquid absorption processes. Impressive volume reduction factors compared to packed columns have been reported, mostly for absorption in chemical solvents (e.g. CO2 post combustion capture with MEA). A very limited number of studies addressed however the potentialities of membrane contactors for physical absorption processes. Moreover, the interplay between volume reduction and energy requirement, which is expected to be of major importance for physical solvents, is unexplored. In this study, a systematic parametric analysis of the intensification and specific energy requirement of membrane contactors for CO2 absorption in 5 different physical solvents is reported. The best flow configuration, module packing fraction and membrane properties (mass transfer performances) are identified for the different solvents. Very high intensification factors compared to the baseline technology (i.e. packed column) are shown to be potentially achievable.

International audience; In light of reducing carbon emissions and the tension on non-renewable energy sources, heat pumps are being investigated as an alternative to fossil-fuel-dependent energy converters in heat demanding applications. On the basis of the impactful results the authors obtained in previous research around the potential of using reactive fluids–instead of inert ones–as novel working fluids in power cycles, the study has been extended to heat pump systems. The thermodynamic analysis of heat pumps operating with reactive gases as working fluids is thus the objective of the present work. More specifically, the analysis is based on the use of instantaneously equilibrated fictive gaseous reactions, with the aim to thoroughly assess the impact of different stoichiometries and thermochemical characteristics of chemical reactions. This studied heat pump is based on the reverse Brayton cycle. Furthermore, the behavior of the fluid in each unit operation of the cycle is investigated and all the results are compared to those of a heat pump utilizing comparable inert fluids; that is to preliminarily quantify the potential gains in performance. For the considered spectrum of reactive fluids, operating conditions, and reaction stoichiometries, the corresponding results show a range of potential reactive fluids that can be utilized in heat pumps and reveal an increase of more than 200% in the system's coefficient of performance compared to inert-fluid heat pumps

The 2-step French process of nuclear waste treatment, which consists in calcining and vitrifying, enable integrating the radio-isotopes into a glassy matrix. The high temperatures involved (above 1000°C) provoke the volatilization of the fission product Cs, in the form of a solid aerosol. Its volatility is increased by the presence of the fission product Tc (simulated by Re). The goal of the work was to characterize the volatilization mechanisms and the retention of the main volatile chemicals in the vitrification process, in order to monitor the volatility from its origin. The first approach was to understand the behavior of the volatile elements in the glass melt, then the transport phenomena to the gas phase, and finally the formation of aerosols. This approach consisted in spiking simplified glass matrices elaborated in a mock-up, with Cs and Re in order to evaluate the effect on volatility. Data treatment was also performed on a series of glass elaborations in a pilot-scale process with diverse elemental concentrations, in order to evaluate the scale-up effects. That led to the conclusion that the Cs-Re volatility comes from the furnace, and to hypothesize about a CsReO4 volatilization mechanism. A second approach was to characterize the evolution of aerosol size distribution throughout the process, and to evaluate the particle capture by a typical dust scrubber. A measurement campaign was performed using an ELPI+ cascade impactor during a glass elaboration on the pilot-scale process. It showed that the aerosol size distribution in the furnace is 1-µm centered. Moreover, MEB-EDS analyses on the particles sampled showed that they are made of solid alkali perrhenates coupled with Mo, that confirm the volatilization mechanism hypothesis. Meanwhile, the characterization of the dust scrubber, with a 1-µm centered simulated alumina aerosol, revealed that the retention is maximized for micronic particles above 2.5 µm., Le procédé français de traitement des déchets nucléaires en deux étapes, calcination et vitrification, permet d’immobiliser les radio-isotopes dans une matrice vitreuse. Les hautes températures mises en œuvre, supérieures à 1000°C, génèrent la volatilisation du produit de fission Cs radioactif, sous la forme d’un aérosol solide. Cette volatilité est accrue en présence du produit de fission Tc (simulé par le Re). L’objectif de ces travaux a été de caractériser les mécanismes de volatilité et la rétention des éléments volatils dans le procédé, dans le but de maitriser la volatilité directement à sa source. Une première approche a visé à comprendre le comportement des éléments chimiques dans les fontes verrières, leur mode de transport jusqu’à la phase vapeur, puis la condensation des aérosols. Cette approche est passée par le dopage de verres simplifiés, élaborés dans une maquette, avec du Cs et du Re dans le but d’en évaluer l’effet sur les volatilités. Elle a été couplée au traitement de données d’un panel d’essais de vitrification sur prototype, mettant en jeu des conditions de concentrations élémentaires variées, dans le but d’évaluer l’extrapolation des phénomènes. Cela a permis de déterminer que l’essentiel de la volatilité Cs-Re provient du four de vitrification, et d’émettre une hypothèse sur le mécanisme de volatilité du CsReO4. Une deuxième approche a été de caractériser l’évolution de la granulométrie des aérosols tout au long du procédé, et d’évaluer la capture des particules par un dépoussiéreur « type » de prototype. Une campagne de mesures a été conduite à l’aide d’un impacteur cascade ELPI+ sur le prototype pendant une élaboration verrière, et a indiqué que la granulométrie dans le four est centrée à 1 µm. En outre, des analyses MEB-EDS des particules prélevées ont révélé qu’il s’agissait de perrhénates d’alcalins solides couplés avec du Mo, ce qui renforce la proposition de mécanisme de volatilité présentée. En parallèle, la caractérisation du dépoussiéreur, à partir d’un aérosol simulé d’alumine centré à 1 µm, a révélé que la rétention est maximale pour des particules microniques au-dessus de 2,5 µm.

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International audience; Membrane contactors offer promising perspectives for intensified gas-liquid absorption processes. A rational design of a membrane based absorption process ideally requires membrane material / solvent compatibility to be evaluated, together to key thermodynamics (i.e. gas solubility) and kinetics data. More specifically, the impact of gas and liquid velocities, as well as solvent loading, on effective mass transfer performances are of major importance for design purposes [1]. Classical, time consuming phase equilibria methods and steady state membrane gas absorption tests with different inlet solvent loadings are most often separately performed in order to determine these different data sets. A fast, compact, easy to use method has been developed in order to quickly assess, through a single experiment, both thermodynamics and mass transfer data (i.e. impact of gas / liquid velocity and solvent loading), based on a batch to continuous approach. The set-up can easily be scaled down (e.g. for systems for which very small volume of solvents are available), extended to multicomponent systems (absorption of different solutes in a given solvent) and used for studies of the influence of temperature or solvent degradation kinetics. These different aspects will be shown and discussed, based on a series of experiments performed with physical and chemical solvents for CO2 absorption from a gaseous mixture.

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International audience; The neutralisation of a simulant of the chemical warfare agent VX (PhX) occurs selectively with lithium ethanolate under classic flow conditions but with moderate reproducibility. Transposed in a custom printed flow reactor, simply feeded with an ethanolic solution of PhX, the formation of EtOLi and the neutralisation are performed in a single operation. Robustness and recyclability of the device is also demonstrated.

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The rigorous description of adsorption isotherms of gases or vapors on solids is of major interest for analytical methods such as chromatography and adsorbent-based separation processes (e.g., PSA)...

The VOC removal from air is a major concern both in the context of occupational and domestic exposure. Membrane processes are often presented as unsuitable for the removal of low concentrated VOCs mainly due to a too low driving force leading to high-energy costs. The aim of the work presented in this paper is to investigate the original combination of a dense membrane separation process and a photocatalytic oxidation process implemented in the permeate compartment of the system for the intensification of the separation and the decomposition of toxic compounds. An unpublished modeling of this coupled processes completed by a robust experimental study integrating the main operating parameters (flow rates, pressures, membrane materials, catalyst mass, concentration, light irradiance) is presented in this work. This exploratory study shows that for a test compound, n-hexane, this approach significantly intensifies the separation of a low-concentration VOC (i.e. 1 to 25 ppm) with a low-energy cost. The model developed here allows designing more enhanced system such as hybrid plug-flow module operating with a thin polydimethylsiloxane membrane and sweep-gas on the permeate compartment. This configuration seems particularly relevant for an efficient VOC separation and limits greatly the presence of potential by-products in the treated effluent, such as formaldehyde, acetaldehyde or carbon monoxide well-known intermediates identified in photocatalysis. From a reaction position, this hybrid process leads to the VOC photocatalytic oxidation advantageously increased compared to a single plug-flow reactor especially for low light irradiances (≈3 W m−2). This process is suitable to work with the solar irradiance.

Carbon monoliths were tested as electrodes for vanadium redox batteries. The materials were synthesised by a hard-templating route, employing sucrose as carbon precursor and sodium chloride crystals as the hard template. For the preparation process, both sucrose and sodium chloride were ball-milled together and molten into a paste which was hot-pressed to achieve polycondensation of sucrose into a hard monolith. The resultant material was pyrolysed in nitrogen at 750 ◦C, and then washed to remove the salt by dissolving it in water. Once the porosity was opened, a second pyrolysis step at 900 ◦C was performed for the complete conversion of the materials into carbon. The products were next characterised in terms of textural properties and composition. Changes in porosity, obtained by varying the proportions of sucrose to sodium chloride in the initial mixture, were correlated with the electrochemical performances of the samples, and a good agreement between capacitive response and microporosity was indeed observed highlighted by an increase in the cyclic voltammetry curve area when the SBET increased. In contrast, the reversibility of vanadium redox reactions measured as a function of the difference between reduction and oxidation potentials was correlated with the accessibility of the active vanadium species to the carbon surface, i.e., was correlated with the macroporosity. The latter was a critical parameter for understanding the differences of energy and voltage efficiencies among the materials, those with larger macropore volumes having the higher efficiencies. This work was supported by ICEEL and Region Grand Est and J.F.V.-V. was hired with these fundings. This work was partly supported by a grant overseen by the French National Research Agency (Pc2TES ANR-16-CE06-0012-01), and the authors involved in it (AC, BK and VF) acknowledge the support of the project's coordinator, Mrs Fouzia Achchaq. This study was partly supported by TALiSMAN project (2019-000214), funded by European Regional Development Fund (ERDF).

The relationship between interfacial and bulk emulsion viscoelasticity is investigated. Water-in-dodecane reverse Pickering emulsions, with a dispersed phase volume fraction of 0.66, stabilized with partially hydrophobic silica particles are addressed. Interfacial and bulk viscoelastic properties are probed via 2D and 3D oscillatory shear rheology. The silica particles concentration and NaCl content have been varied. In the whole range of concentrations studied the elastic modulus (G′) remains always greater than the viscous modulus for 2D and 3D rheology. The viscoelastic behavior can be related to the silica concentration both at the interface and in the emulsion. Power law dependences towards the silica content are recorded for the interfacial and the bulk emulsion elastic modulus. When increasing the NaCl concentration, the viscoelastic properties both at the interface and in the emulsion become stronger. The amount of silica and NaCl produces similar effects on both the interface and bulk viscoelastic properties. The increase of their concentration induces a rigidification of the dodecane/water interface since G P ′ (interface) increases. Such interfacial hardening produces a rigidification of the droplets ( G P ′ (Emulsion) is enhanced). Correlations between the interfacial and bulk emulsion viscoelasticity are also extracted from the experimental data. This is the first time that these kinds of relationship are reported. These results highlight that everything that affects the interfacial viscoelasticity is reflected on the bulk scale of emulsions.

International audience; Three-dimensional (3D) printing in soil science is relatively rare but offers promising directions for research. Having 3D-printed soil samples will help academics and researchers conduct experiments in a reproducible and participatory research network and gain a better understanding of the studied soil parameters. One of the most important challenges in utilizing 3D printing techniques for soil modeling is the manufacturing of a soil structure. Until now, the most widespread method for printing porous soil structures is based on scanning a real sample via X-ray tomography. The aim of this paper is to design a porous soil structure based on mathematical models rather than on samples themselves. This can allow soil scientists to design and parameterize their samples according to their desired experiments. An open-source toolchain is developed using a Lua script, in the IceSL slicer, with graphical user interface to enable researchers to create and configure their digital soil models, called monoliths, without using meshing algorithms or STL files which reduce the resolution of the model. Examples of monoliths are 3D-printed in polylactic acid using fused filament fabrication technology with a layer thickness of 0.20, 0.12, and 0.08 mm. The images generated from the digital model slicing are analyzed using open-source ImageJ software to obtain information about internal geometrical shape, porosity, tortuosity, grain size distribution, and hydraulic conductivities. The results show that the developed script enables designing reproducible numerical models that imitate soil structures with defined pore and grain sizes in a range between coarse sand (from 1 mm diameter) to fine gravel (up to 12 mm diameter).

Stem cell-based therapeutic products could be the key to treat the deadliest current pathologies, ranging from neuro-degenerative to respiratory diseases. However, in order to bring these innovative therapeutics to a commercialization stage, reproducible manufacturing of high quality cell products is required. Although advances in cell culture techniques have led to more robust production processes and dramatically accelerated the development of early-phase clinical studies, challenges remain before regulatory approval, particularly to define and implement science-based quality standards (essential pre-requisites for national health agencies). In this regard, using new methodologies, such as Quality By Design (QBD), to build the production process around drug quality, could significantly reduce the chance of product rejection. This review-based work aims to perform a QBD approach to Mesenchymal Stem Cell (MSC) manufacturing in standard two-dimensional flasks, using published studies which have determined the impact of individual process parameters on defined Critical Quality Attributes (CQA). Along with this bibliographic analysis, parameter criticality was determined during the two main manufacturing stages (cell extraction and cell amplification) along with an overall classification in view of identifying the Critical Process Parameters (CPP). The analysis was performed in view of an improved standardization between research teams, and should contribute to reduce the gap towards compliant Good Manufacturing Practice (cGMP) manufacturing.

In this study, phenolic compounds from an aqueous protein by-product from rapeseed meal (RSM) were identified by HPLC-DAD and HPLC-ESI-MS, including sinapine, sinapic acid, sinapoyl glucose, and 1,2-di-sinapoyl gentibiose. The main phenolic compound in this by-product was sinapine. We also performed acid hydrolysis to convert sinapine, and sinapic acid derivatives present in the permeate, to sinapic acid. The adsorption of phenolic compounds was investigated using five macroporous resins, including XAD4, XAD7, XAD16, XAD1180, and HP20. Among them, XAD16 showed the highest total phenolic contents adsorption capacities. The adsorption behavior of phenolic compounds was described by pseudo-second-order and Langmuir models. Moreover, thermodynamics tests demonstrated that the adsorption process of phenolic compounds was exothermic and spontaneous. The highest desorption ratio was obtained with 30% (v/v) and 70% (v/v) ethanol for sinapine and sinapic acid, respectively, with a desorption ratio of 63.19 ± 0.03% and 94.68 ± 0.013%. DPPH and ABTS tests revealed that the antioxidant activity of the hydrolyzed fraction was higher than the non-hydrolyzed fraction and higher than the one of vitamin C. Antioxidant tests demonstrated that these phenolic compounds could be used as natural antioxidants, which can be applied in the food industry.

International audience; Correlation of the mass transfer characteristics of microfluidic parallel-plate electrochemical reactors is proposed for the first time. Firstly, the variation in the mass transfer coefficient (k m) (1.61-3.94 × 10 − 5 m s − 1) over a wide range of interelectrode distances (d elec) from millimetric (3 mm) to micrometric values (100 µm) is reported. Secondly, a drastic slope change in the curve makes it possible to identify the onset of microfluidic behavior in a quantitative way for the first time, i.e. below a 1000 µm gap. Thirdly, a mathematical model is proposed which predicts k m for any d elec of interest. Fourthly, under laminar flow (7 < Reynolds (Re) < 623) and for temperatures in the range of 10-50 • C (532 < Schmidt (Sc) < 3315), new Sherwood (Sh) correlations are obtained for both microfluidic and millimetric configurations. It is thus feasible to extrapolate k m for microfluidic electrochemical reactor scale-up.

Cancer is the second leading cause of death worldwide after cardiovascular disease. Depending on the type and the location of the tumor, several cancer treatments are implemented. Among these, the three most conventional therapies are surgery, radiotherapy and chemotherapy. However, there are other therapeutic approaches such as photodynamic therapy (PDT). PDT relies on the combined action of light, a photoactivable molecule called photosensitizer (PS) and molecular oxygen. Most of the PSs used for clinical applications are not cancer-cell specific. One of the solutions to overcome this problem is the use of nanoparticles (NPs) to induce a passive targeting. It is also possible to graft a vector onto the NPs to specifically target membrane receptors overexpressed in the tumor cells or neovessels surrounding the tumor. In this review, we focus on the NPs loaded with PSs and coupled to peptides for targeted PDT. We described nanosystems that targeted Neuropilin-1 (NRP-1), αvβ3 integrins, nucleolin membrane receptor, epidermal growth factor (EGF) receptor, protein-glutamine-gamma-glutamyltransferase (TGM2), p32, transferrin, PD-1, and mitochondrial membrane. The use of a cell absorbing-peptide is also described.

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International audience; Combined cooling, heating, and power (CCHP) systems enable the simultaneous supply of electricity, heating, and cooling, thus meeting the major energy needs of humans in a single device. Conventional CCHP systems consist of the combination of a prime mover, heating, and cooling system, each of them operating with a thermodynamically suitable working fluid. Recently, novel CCHP cycles, based on the use of a single working fluid for the whole operation, have been proposed. Since the choice of the working fluid represents a design challenge in the development of such technologies, in this work, a product design approach for the selection of suitable working fluids for emergent CCHP applications is presented. A database search is implemented to screen about 60 000 structures included in the DDB, the Design Institute for Physical Properties, and the NIST TDE databases. The screening considers thermodynamic, process-related, constructional, safety, and environmental constraints. Moreover, the tc-PR equation of state is used to ensure the quality of the calculation of thermophysical properties and the performance assessment of promising working fluids. This study shows that flammable fluids such as vinylacetylene or HFC-152 have a good potential for CCHP applications. In the case of reinforced safety restrictions, HCFO-1233zd(E) seems to be an interesting candidate since it is nonflammable and nontoxic.

International audience; Chemical Product Engineering (CPE) is marked by numerous challenges, such as the complexity of the properties–structure–ingredients–process relationship of the different products and the necessity to discover and develop constantly and quickly new molecules and materials with tailor-made properties. In recent years, artificial intelligence (AI) and machine learning (ML) methods have gained increasing attention due to their performance in tackling particularly complex problems in various areas, such as computer vision and natural language processing. As such, they present a specific interest in addressing the complex challenges of CPE. This article provides an updated review of the state of the art regarding the implementation of ML techniques in different types of CPE problems with a particular focus on four specific domains, namely the design and discovery of new molecules and materials, the modeling of processes, the prediction of chemical reactions/retrosynthesis and the support for sensorial analysis. This review is further completed by general guidelines for the selection of an appropriate ML technique given the characteristics of each problem and by a critical discussion of several key issues associated with the development of ML modeling approaches. Accordingly, this paper may serve both the experienced researcher in the fieldas well as the newcomer.

International audience; 3-Mercaptopropionic acid (MPA)-capped Mn-doped ZnSe/ZnS and CdTe/CdS core/shell quantum dots (QDs) were prepared via a mild aqueous phase process. The synthesis conditions were adjusted to yield QDs with roughly similar nanocrystal average diameter and light emission wavelengths. X-ray powder diffraction, transmission electron microscopy and spectrofluorometry have been used to characterize the crystal structure and optical properties of the as-prepared QDs. Growth inhibition tests using E. coli bacterial cells were also carried out to assess the cytotoxicity of the dots and showed that core/shell ZnSe:Mn/ZnS@MPA QDs do not exhibit any cytotoxicity against E. coli cells up to a concentration of 14 μM while at this concentration CdTe/CdS@MPA core/shell QDs exert a severely more pronounced cytotoxicity. These results indicate that the cytotoxicity is likely associated to the presence of Cd in the chemical composition of CdTe/CdS@MPA QDs and that ZnSe:Mn/ZnS@MPA nanocrystals are safer and could be used as biological probes for cells and tissues imaging.

International audience; Metal-chelating peptides (MCP) are considered as indirect antioxidants due to their capacity to inhibit radical chain reaction and oxidation. Here, we propose a new proof of concept for the screening of MCPs present in protein hydrolysates for valorizing their antioxidant properties by using the emerging time-resolved molecular dynamics technology, switchSENSE. This method unveils possible interactions between MCPs and immobilized nickel ions using fluorescence and electro-switchable DNA chips. The switchSENSE method was first set up on synthetic peptides known for their metal-chelating properties. Then, it was applied to soy and tilapia viscera protein hydrolysates. Their Cu2+-chelation capacity was, in addition, determined by UV-visible spectrophotometry as a reference method. The switchSENSE method has displayed a high sensitivity to evidence the presence of MCPs in both hydrolysates. Hence, we demonstrate for the first time that this newly introduced technology is a convenient methodology to screen protein hydrolysates in order to determine the presence of MCPs before launching time-consuming separations.

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The oxidative coupling (OCM) and the partial catalytic oxidation (POM) of methane as well as the homogeneous oxidation of methane (HOM) differ only in the ratio CH4/O2 used and of course in the use of a catalyst. It can therefore be considered that their overall reaction mechanism should be the same with elementary reactions of varying importance depending on the type of oxidation reaction studied. We have therefore tried to represent the results obtained during the experimental study of OCM and POM over La2O3 and that of the oxidation of methane in gas phase from a single mechanism. At high temperature, OCM and POM are catalytic reactions but their reaction mechanisms are very complex because the surface reactions are coupled to reactions in gas phase by the intermediary of radicals, so both homogeneous and heterogeneous mechanisms occur at the same time. In this work, the development and the validation of a hetero-homogeneous mechanism is proposed for the three reactions. This mechanism is based on elementary steps at the catalyst surface and elementary steps in gas phase for a large range of temperature (973 K–1173 K) and residence time (0.7 s–5.5 s).

International audience; This work addresses the polygeneration concept integrating concentrating solar power (CSP) with an organic Rankine cycle (ORC) to produce electricity and drinking water by hybrid desalination process combining reverse osmosis (RO) and low-temperature multi-effect distillation (LTMED). Experiments carried out on a bench scale RO pilot led to determine optimal operating parameters as well as options to mitigate the main limiting factors of this technology by hybridizing with LTMED. These data helped to simulate a large scale solar polygeneration plant integrating parabolic trough collectors as CSP technology and a hybrid RO-LTMED system as desalination technology. Various ORC design proposals were simulated and the optimal configuration was pointed out on the basis of thermodynamic criteria (energy efficiency and exergy destruction) and an economic analysis by using two working fluids: an alkane commonly admitted as good candidate and an ester proposed here as green alternative. Results obtained in this work contribute positively to extending the solar polygeneration for desalination and production of energy leading to future sustainable plants.

International audience; It is presented for the first time the occurrence and modelling of cathodic mineral electro-precipitation in microfluidic thin-film configuration of electrochemical advanced oxidation process (EAOP), in order to better understand and predict the cathode's scaling when treating water containing Mg2+ and Ca2+. Upon a systematic study, the main results show that when an inter-electrode distance of 500 µm is used at 4 mA cm−2, local alkalization on cathode surface occurs despite the absence of dissolved O2 suggesting that it takes place due predominantly to water reduction (current efficiency > 99%) and not dissolved O2 reduction. Moreover, electromigration phenomenon could be neglected when varying ionic strength from 0.02 to 0.1 mol L−1, while diffusion was the kinetic rate-limiting step. In addition, Ca(OH)2 and MgCO3 precipitates were not formed under all investigated conditions. Mg(OH)2 electro-precipitation was found to be highly dependent on current density, but independent of other ionic species jointly present in electrolyte. Mg(OH)2 precipitated once interfacial pH of 10.2 was reached. More CaCO3 was electro-precipitated at lower current density (ca. 7.2%) owing to more vigorous gas evolution when higher current density was applied. 12% less CaCO3 electro-precipitation was found in the presence of Mg2+ confirming its inhibiting effect towards CaCO3 scaling. The mathematical model proposed could fit well the experimental curves (Root mean square error (RMSE) < 0.1163) and permit to predict the evolution of concentration of depositing species (i.e. Mg2+, Ca2+ and CO32−). Furthermore, the role of hydroxyl radicals (•OH) produced at boron-doped diamond (BDD) anode could be neglected upon the applied conditions, meaning that the outcome of this study is reliable across all types of water containing Mg2+, Ca2+ and/or CO32− in compliance to their ubiquity when it is to be treated by electrolysis in general

International audience; Generated by zinc hydrometallurgical production and containing several toxic species, jarosite has been little used or beneficiated to date. Utilization of jarosite can save mining resources by producing valuable products, and reduce potential hazards from jarosite disposal. To avoid high energy consumption as in the roasting steps of the current jarosite process, hydrometallurgy has been used in the various steps of an original process aimed at producing valuable zinc-iron alloys from industrial jarosite waste. The process designed consists of three main steps: (i) jarosite leaching by sulfuric acid solutions yielding Fe(III) and Zn(II) species; (ii) reduction of Fe(III) to Fe(II) upon addition of industrial blende; and (iii) electrodeposition of the alloy from the recovered acidic Fe-Zn solution. Care was also taken to limit the amount of alkali to be added by maintaining the pH in a narrow range; moreover, no specific additives were employed. The various steps of the process have been investigated and the most suitable conditions for high yields have been identified. Among the various impurities in the minerals used and recovered from the acidic solution, copper ions had to be removed by preferential electrodeposition prior to deposition of Zn-Fe alloys. Nevertheless, these results indicated the need for a divided cell to avoid galvanic interference in this last operation from the Fe(II)/Fe(III) couple, which was found to reduce the faradaic yield for alloy deposition from 69% in the first minutes to 30% after 30 minutes.

International audience; Scope: Food allergy to sunflower seed (SFS) protein is not frequent and only non-specific lipid transfert protein (nsLTP) Hel a 3 is officially recognized as a food allergen. Out of the eleven seed storage 2S-albumins (SESA) detected in SFS, only SFA-8 allergenicity has been investigated so far. The study aimed then to evaluate SFS protein allergenicity and particularly, to compare the sensitization potency of SESA in a mouse model. Methods and Results: The most abundant SESA and nsLTP were isolated from SFS through a combination of chromatographic methods. Purified proteins were then used to measure specific IgG1 and IgE responses in BALB/c mice orally sensitized to different SFS protein isolates. The study, thus, confirmed the allergenicity of SFA-8 and Hel a 3 but mice were also highly sensitized to other SESA such as SESA2-1 or SESA20-2. Furthermore, competitive inhibition of IgE-binding revealed that SFA-8 IgE-reactivity was due to cross-reactivity with other SESA. 11S-globulins were weakly immunogenic and were rapidly degraded in an in vitro model of gastroduodenal digestion. In contrast, Hel a 3, SESA2-1 and SFA-8 were more resistant to proteolysis and gastroduodenal digestion did not affect their IgE-reactivity. Conclusions: SESA2-1 or SESA20-2 were more potent allergens than SFA-8 in this mouse model. Allergenicity of SESA must be now confirmed in SFS-allergic patients.

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L'auteur a souhaité limiter l'accès aux membres de l'Enseignement supérieur français jusqu'au 12 juillet 2022; Since fluorescence imaging (FI) and magnetic resonance imaging (MRI) are among the most effective diagnostic tools, QDs with fluorescent and magnetic properties are of great interest as dual-modal probes. In this work, undoped and doped Ag-In-Zn-S (AIZS) and Ag-In-Ga-Zn-S (AIGZS) QDs were synthesized and investigated as bimodal probes for FI and MRI. Highly fluorescent AIZS QDs were prepared in organic media using DDT and OAm as capping ligands. Mn:AIZS QDs showed paramagnetic and superparamagnetic properties. AIZS and Mn:AIZS QDs were also transferred into aqueous phase using the amphiphilic PMAO polymer. Further, Mn, Gd or Fe-doped AIZS QDs were prepared in aqueous media, showed low cytotoxicity toward KB cells, and demonstrated potential as fluorescent probes for FI. Finally, AIGZS and Mn:AIGZS QDs, synthesized via a novel single precursor thermal decomposition method, showed high fluorescence and paramagnetic/superparamagnetic properties. Mn-doped aqueous transferred AIGZS QDs increased contrast in both T1-weighted and T2-weighted images with increasing in Mn loading.; L’imagerie par fluorescence (IF) et l’imagerie de résonance magnétique (IRM) comptent parmi les outils de diagnostic les plus efficaces. Dans ce contexte, des QDs possédant à la fois des propriétés fluorescentes et magnétiques sont d’un grand intérêt en tant que sondes bimodales. Dans ce travail, des QDs Ag-In-Zn-S (AIZS) et Ag-In-Ga-Zn-S (AIGZS) ont été préparés et dopés afin de développer de nouvelles sondes de sondes bimodales pour l’IF et l’IRM. Des QDs AIZS très fluorescents ont été préparés en milieu organique à l’aide de DDT et d’OAm comme ligands. Les QDs Mn:AIZS possèdent des propriétés paramagnétiques et superparamagnétiques. Les QDs AIZS et Mn:AIZS ont également été transférés en phase aqueuse à l’aide du polymère amphiphile PMAO. Par la suite, des QDs AIZS dopés Mn, Gd ou Fe ont été préparés en milieu. Des études toxicologiques et d’imagerie ont montré une bonne biocompatibilité avec les cellules KB ainsi que le fort potentiel de ces nanocristaux pour l’IF. Dans la dernière partie de ce travail, des QDs AIGZS and Mn:AIGZS QDs ont été préparés via un procédé de décomposition thermique n’utilisant qu’un seul précurseur. Ces QDs possèdent de très bonnes propriétés optiques et magnétiques. Les QDs dopés Mn ont été transférés en phase aqueuse et ont montré un fort potentiel comme agent de contraste pour l’imagerie T1 et T2.

International audience

It is necessary and emergent to reduce our dependence to fossil resource and to mitigate climate change. In this context, biomass becomes a strategic renewable resource, for the production of green energy, chemicals and high value materials. Lignocellulosic biomass is the most abundant non-edible feedstock for the synthesis of carbonaceous fuels or chemicals. One important fraction of lignocellulosic biomass is lignin, which is a highly heterogeneous aromatic macromolecule that resists bio-degradation to a much greater extent than cellulosic components. The pulp and paper industry is the largest producers of extracted lignin. Lignin is primarily treated as a by-product and it is valorized for heat and power production. However, this lignin has great potential for value-added development that can capitalize on the unique aromatic features of lignin to potentially replace certain types of petroleum-derived products. In this thesis, industrially available lignins were first characterized. The research focus is to depolymerize these lignins to monomers or oligomers of potential interest for biomaterials synthesis. Both reductive (under H2) and oxidative (O2) liquefaction atmospheres are presented. Among the most significant challenges with lignin liquefaction research is the effective characterization of the resulting liquid phase products. In order to address this issue, a novel analytical technique utilizing UV-fluorescence spectroscopy is introduced for rapid screening of lignin liquefaction products. This technique is assessed in conjunction with other analytical methods, which are compared and contrasted. Different catalysts, solvents (ethanol, NaOH) and conditions have been studied. A global process analysis including some technical-economical assessment gives the main process unit to improve for a better valorisation of lignins on a real case pulp & paper mill., Il est important de réduire notre dépendance aux ressources fossiles et le réchauffement climatique. Dans ce contexte, la biomasse est une ressource renouvelable stratégique pour la production d’énergie, de composés chimiques et de matériaux. La biomasse lignocellulosique est la biomasse non alimentaire la plus abondante. La lignine représente une fraction importante de cette biomasse. C’est une macromolécule avec des motifs variés principalement constitués de noyaux aromatiques. L’industrie de production de la pâte à papier produit une importante quantité de lignine qui est principalement valorisée par combustion pour produire de la chaleur et de l’électricité. Mais des composés à plus haute valeur ajoutée pourraient être produits à partir de la lignine comme notamment des composés aromatiques (phénols, etc.). Durant cette thèse, nous avons tout d’abord caractérisé des lignines techniques disponibles au niveau industriel. Puis, l’objectif est de dépolymériser ces lignines en monomères (phénols) ou oligomères en vue de produire des polymères à haute-valeur ajoutée. Nous avons étudié une dépolymérisation en milieu liquide (« liquéfaction ») en présence d’hydrogène ou d’oxygène. La liquéfaction produit une large gamme de composés qui est difficile à analyser. Nous avons proposé la fluorescence UV comme une technique rapide et simple pour analyser les liquides. Cette méthode d’analyse a été comparée à d’autres techniques comme la GPC ou le MALDI-TOFMS. Différents catalyseurs, solvants (eau/NaOH ou éthanol), conditions (températures) ont été testés. Les rendements en monomères restent faibles pour toutes ces conditions du fait du caractère très réticulé de ces lignines industrielles. Une modélisation globale du procédé est proposée pour évaluer les procédés de liquéfaction intégrés dans une unité Kraft de production de pâte à papier industrielle.

L'auteur a souhaité limiter l'accès aux membres de l'Enseignement supérieur français jusqu'au 8 juillet 2022; Quantum dots (QDs) have high potential for biological detection, photovoltaics and catalysis due to their unique photophysical properties. The most studied semiconductors contain heavy metals such as cadmium and lead and their fields of application are very limited. As part of this thesis, we developed new aqueous synthesis processes for ternary QDs AgInS₂ and quaternary AgInS₂/ZnS and studied their doping by the Ni(+2) and Co(+2) cations to prepare nanocrystals with fluorescent and magnetic properties. We first optimized the synthesis of AIZS QDs in aqueous media using 3-MPA as ligand and produced nanocrystals with a fluorescence quantum yield of 65%. Then, the doping of these nanocrystals by cations Ni(2+) and Co(2+) was studied. A drop in quantum fluorescence efficiency is observed after doping. The best magnetic properties were observed at low temperature (10 K) and the magnetization values increase with the dopant concentration. The AIZS QDs have been associated with the ZnO nanorods by heterojunction to form a good photocatalyst ZnO/AIZS(10%) which degrades 98% of the Orange II in visible during 90 min under intensity 40 W/cm². This material can be reused, its photocatalytic activity only slightly decreases after 8 cycles (91% photodegradation).; Les quantum dots (QDs) ont un fort potentiel pour la détection biologique, le photovoltaïque et la catalyse en raison de leurs propriétés photophysiques uniques. Les semiconducteurs les plus étudiés contiennent des métaux lourds comme le cadmium et le plomb et leurs domaines d’applications sont très limités. Dans le cadre de cette thèse, nous avons développé de nouveaux procédés de synthèse en milieu aqueux des QDs ternaires AgInSAgInS₂ et quaternaires AgInS₂/ZnS et avons étudié leur dopage par les cations Ni²⁺ et Co²⁺ afin de préparer des nanocristaux dotés de propriétés fluorescentes et magnétiques. Nous avons tout d’abord optimisé la synthèse des QDs AIZS en milieu aqueux en utilisant le 3-MPA comme ligand et avons produit des nanocristaux avec un rendement quantique de fluorescence de 65%. Puis, le dopage de ces nanocristaux par les cations Ni(+2) et Co(+2) a été étudié. Une chute du rendement quantique de fluorescence est observée après le dopage. Les meilleures propriétés magnétiques ont été observées à basse température (10 K) et les valeurs d'aimantation augmentent avec la concentration en dopant. Les QDs AIZS ont été associés aux nanotiges ZnO par hétérojonction pour former un bon photocatalyseur ZnO/AIZS(10%) qui dégrade 98% de l’Orange II en visible dans 90min sous intensité 40W/cm². Ce matériau est recyclable, vu que son activité photocatalytique ne baisse que légèrement après 8 cycles (91% de photodégradation).

International audience

International audience; Carbon nanotubes and graphene have a combination of remarkable properties: lightness, high surface area, good stability, superior thermal and electrical conductivity and high mechanical properties. These properties confer to them an undisputable potential to develop sustainable technologies. Energy and environmental applications are especially concerned since they involve surface phenomena and require high rate interface transfer. Carbon nanomaterials can be considered as a platform for which a targeted chemical modification is able to generate a specific functionality and interactions. This paper describes several types of chemical treatment applied to graphene nanosheets or carbon nanotubes. And some examples of application of these chemically modified carbon nanomaterials are given including support to immobilize enzymes for green chemistry and conductive additive for heat transfer fluids.

The chemistry underlying liquid-phase oxidation of organic compounds, the main cause of their aging, is characterized by a free-radical chain reaction mechanism. The rigorous simulation of these phenomena requires the use of detailed kinetic models that contain thousands of species and reactions. The development of such models for the liquid phase remains a challenge as solvent-dependent thermokinetic parameters have to be provided for all the species and reactions of the model. Therefore, accurate and high-throughput methods to generate these data are required. In this work, we propose new methods to generate these data, and we apply them for the development of a detailed chemical kinetic model for n-butane autoxidation, which is then validated against literature data. Our approach for model development is based on the work of Jalan et al. [J. Phys. Chem. B 2013, 117, 2955-2970] who used Gibbs free energies of solvation [ΔsolvG(T)] to correct the data of the gas-phase kinetic model. In our approach, an equation of state (EoS) is used to compute ΔsolvG as a function of temperature for all the chemical species in the mechanism. Currently, ΔsolvG(T) of free radicals cannot be computed with an EoS and it was calculated for their parent molecule (H-atom added on the radical site). Theoretical calculations with the implicit solvent model were performed to quantify the impact of this assumption and showed that it is acceptable for radicals in n-butane and probably in all n-alkanes. New rate rules were proposed for the most important reactions of the model, based on theoretical calculations and the literature data. The developed detailed kinetic model for n-butane autoxidation is the first proposed model in the literature and was validated against the experimental data from the literature. Simulations showed that the main autoxidation products, sec-butyl hydroperoxides and 2-butanol, are produced from H-abstractions from n-butane by sec-C4H9OO radicals and the C4H9OO + C4H9OO reaction, respectively. The uncertainty of the product ratio ("butanone + 2-butanol"/"2-butoxy + 2-butoxy") of the latter reaction remains high in the literature, and our simulations suggest a 1:1 ratio in n-butane solvent.

International audience; Advanced oxidation processes (AOPs) have received a lot of attention over the years as advanced physicochemical polishing wastewater treatments to remove biorefractory pollutants. Additionally, many studies report their excellent degradation and mineralization performance as stand-alone technologies too, demonstrating the versatility of these processes; however, there is a lack of suitable methods to compare the performance (in terms of removal efficiency and operating costs) of different AOPs in the same conditions. In this context, the goal of this paper is to propose a systematic investigation by introducing a novel criterion, namely the accumulated oxygen-equivalent chemical-oxidation dose (AOCD), to systematically compare the diverse AOPs available: ozonation, H2O2 photolysis, Fenton, photo-Fenton, electro-Fenton and photoelectro-Fenton (paired with anodic oxidation, for the latter two). For each of these, the cost efficiency was determined by optimizing the operating conditions for the removal of phenol, selected as a model pollutant (1.4 mM, equivalent to 100 mg-C L-1). The operating costs considered sludge management, chemical use and electricity consumption. Among all AOPs, electro-Fenton was the most cost-effective (108-125 € m-3), notwithstanding the mineralization target (50%, 75% and 99%), owing to its electrocatalytic behavior. Chemical Fenton proved competitive too up to 50% of mineralization, meaning that it could also be considered as a cost-effective pre-treatment solution. AOCD was the lowest for electro-Fenton, which could be attributed to its excellent faradaic yield, while UV-based processes generally required the highest dose. The AOCD criterion could serve as a baseline for AOP comparison and prove useful for the legislator to determine the "best available techniques" as defined by the Industrial Emissions European Union Directive 2010/75/EU.

Pervaporation (PV) has mainly been used for dehydration in industrial applications as well as for the recovery of some organic components from various organic or water mixtures. Nevertheless, to date, pervaporation has never been seen as a potential industrial solution to get drinkable water by water permeation, contrarily to membrane distillation (MD). Nevertheless, at the lab scale, some studies with hydrophilic PV membranes have been reported. This work intends to underline the potential industrial interest of hydrophobic PV composite membranes for desalination. Indeed, even in hypersaline solutions, the water activity remains very high (>0.9), and it is wise to use membranes with stable properties in water to guarantee steady performance. Therefore, this study investigates the interest of hydrophobic polymers as coating selective layers for desalination. To guide our choice, a rational approach was used based on the prediction of the membrane resistance to water transfer. Polymethylpentene, poly(1-trimethylsilyl-1-propyne) and Teflon™ AF2400 were tested as the top layer to obtain hydrophobic composite PV membranes. Several feed NaCl solutions with or without a surfactant were used to investigate the mass transfer properties of these PV membranes for water treatment comparatively to more conventional porous membranes (e.g. PVDF) currently studied in membrane distillation.

Curcumin is a naturally occurring hydrophobic polyphenol compound. It exhibits a wide range of biological activities such as antibacterial, anti-inflammatory, anti-carcinogenic, antifungal, anti-HIV, and antimicrobial activity. In this research work, antimicrobial curcumin nanofibrous membranes are produce by an electrospinning technique using the Eudragit RS 100 (C19H34ClNO6) polymer solution enriched with curcumin. The morphology and chemistry of the membrane are analyzed using scanning electron microscopy (SEM) and Fourier transform infrared (FTIR) spectroscopy. Kirby Bauer disk diffusion tests are carried out to examine the antibacterial effectiveness of the membrane. Experimental results show that the nanofibers produced are of uniform thickness morphology and curcumin is successfully incorporated into the nanofibrous mat, while no chemical bonding was observed between curcumin and the polymer. The antimicrobial curcumin nanofibrous membranes can be effectively applied as antimicrobial barrier in a wide variety of medical applications such as wound healing, scaffolds, and tissue engineering.

International audience; This work aims at studying the expanding and breakup dynamics of the thread of a controllable dispersed phase under different flow rates in a microfluidic flow-focusing device. The whole formation process of ferrofluid droplets under no magnetic field (NM), a radial magnetic field (RM) and an axial magnetic field (AM) were investigated and compared. It was found that the volume of the ferrofluid droplets can be actively controlled by the applied magnetic field. The radial magnetic field and axial magnetic field affect mainly the expanding and breakup processes of the thread, respectively. The influence of the flow rates, magnetic flux density and magnetic field direction on the formation and breakup processes were extensively studied. The variation of the minimum width of the ferrofluid thread with the remaining time could be scaled with a power law.

International audience

International audience; The efficient, versatile and straightforward synthesis of the first N-alkyl analogs of induline 3B (8a and 8b) is reported. Thanks to the introduction of lipophilic substituents and its attractive photophysical properties (far-red emission and production of singlet oxygen), phenazinium 8b can be used as theranostic agent and shows, at very low concentration (100 nM), a remarkable ability to: i) image cells and zebrafish embryos with high quality under both mono (514 nm) and biphotonic (790 and 810 nm) excitations, ii) efficiently and quickly penetrate cancer cells rather than healthy fibroblast, iii) induce a total or almost total cancer cell death in vitro and in vivo after illumination (exc = 540-560 nm). The molecular structure of 8b is based on a triamino-phenazinium core only, with no need for additional components, highlighting the emergence of a minimalistic and versatile class of fluorescent probes for targeted photodynamic cancer therapy.

International audience; The perturbed chain-statistical associating fluid theory (PC-SAFT) equation of state (EoS) is applied, and its performance is assessed using a reliable free-to-access benchmark thermodynamic database developed by the authors. A total of 200 non-electrolytic binary systems are included in the database, which are divided into nine groups according to the associating character of the components, that is, their ability to be involved in a hydrogen bond. The properties based on which the assessment is performed include two-phase vapor–liquid and liquid–liquid equilibrium, three-phase vapor–liquid–liquid equilibrium, critical point, azeotropic point, enthalpy of mixing, and heat capacity of mixing data. A specific procedure for the calculation of deviations between model predictions and experimental data and for grading the thermodynamic model is applied based on a previously published proposed methodology. The PC-SAFT EoS is implemented with classical mixing rules, no induced association scheme, and no regressed binary interaction parameters. The results are discussed, and specific characteristics of model performance with respect to different families of mixtures are analyzed

This work presents a comprehensible approach based on the application of characteristic times and Damkohler numbers to optimize the synergy between catalytic reaction, heat exchange and membrane separation for an exothermic balanced reaction. This approach allows the description of parameters required to reduce limitations and intensify the process, considering the DME direct synthesis from a CO2-rich feedstock as a case study. Different couplings are dealt with: reaction and heat exchange; reaction and separation; and reaction, heat exchange and separation. Coupling to a heat exchange enables to follow an optimal temperature progression and minimize the reactor volume by maximizing the reaction rate at any position, allowing the design of compact equipment adapted to delocalized production. Coupling to a membrane increases the achievable conversion at a given temperature. A trade-off between these functions is necessary to achieve the optimal conditions. Appropriate heat exchange enables proper membrane operation. Coupling to a separation improves the performance of a reactor-heat exchanger configuration. 85% of CO2 conversion may be achieved. An optimization of the catalyst distribution is proposed, reducing the total catalyst mass by 21% and hot spot intensity by about 20 °C compared to a uniform catalyst distribution for an identical outlet conversion.

International audience; Minerals are essential to different biological processes in living beings. Likewise, free transition metals such as copper and iron promote the formation of reactive oxygen species (ROSs). However, metal-binding peptides obtained by enzymatic hydrolysis of proteins or synthesized by solid-phase peptide synthesis avoid ROS formation catalyzed by free transition metals. Interactions between metals and mineral-binding peptides (MBPs) are usually studied using spectroscopic techniques, isothermal titration calorimetry, and more recently by surface plasmon resonance and switchSENSE. Through electrospray ionization-mass spectrometry, the changes in the binding affinities can be studied. MBPs can be purified using immobilized metal-ion affinity chromatography, and its process simulation. Various cellular models are used to investigate the health effects of MBPs.

International audience

OBJECTIVES: The direct assessment of ileal samples of amino acid (AA) digestibility is invasive in humans. A less invasive but indirect method, namely « dual tracer » was recently developed. It relies on the plasma isotopic enrichment ratio of two labeled protein, a reference protein or alternately AAs labeled with (13)C and the test protein labeled with (15)N. This recent method has not yet been challenged against direct measurement of ileal digestibility. METHODS: Seven healthy volunteers were intubated with naso-ileal tube. Every 30min for 4h, they ingested sunflower biscuits containing a total of 25g of (15)N intrinsically labeled sunflower protein isolate. They also ingested 60g chocolate containing a total of 400mg of a mix of (13)C algal individual AAs. Ileal contents were collected continuously for 8h following the first meal and plasma was sampled every 30min for 4h and hourly between 4 and 8h. (15)N and (13)C indispensable amino acid (IAA) ileal digestibility were determined by measuring (15)N and (13)C enrichment in AAs by GC-C-IRMS and AA content by UHPLC in ileal effluent. Plasma and meal (15)N and (13)C IAA enrichment were measured by GC-C-IRMS. Isotopic (15)N/(13)C ratio were determined using area under the curve value for each isotope. RESULTS: Using direct ileal sampling, average IAA ileal digestibility was: (i) 88.5 ± 5.0% for sunflower isolate ((15)N) with values ranged from 85.8 ± 5.1% for threonine to 91.1 ± 5.8% for methionine, and (ii) 97.6 ± 1.7% for free AAs (13C) with values ranged from 95.9 ± 2.3% for lysine to 98.8 ± 0.8% for phenylalanine. With the “dual tracer” method, digestibility of isoleucine, leucine, threonine and valine was significantly lower than with ileal determination (from 7.9% for threonine to 24.3% for leucine), Methionine and phenylalanine values were aberrant (over 100%) For lysine, the difference between the two methods was not statistically different (4.7%, p = 0.49). CONCLUSIONS: With our methodological conditions, the “dual tracer” method provides physiological values for most IAA except methionine and phenylalanine. However, values were low compared to ileal digestibility (about 10%) and interindividual variability was high. This less invasive method is promising but requires methodological improvements. FUNDING SOURCES: French Research National Agency (ANR), financial support of SOFIPROTEOL under the FASO Project PRODIAL.