7 results on '"Chaplais, Gérald"'
Search Results
2. Impact of Compression on the Textural and Structural Properties of CPO-27(Ni).
- Author
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Trierweiler Gonçalves, Gabriel, Michelin, Laure, Josien, Ludovic, Paillaud, Jean-Louis, and Chaplais, Gérald
- Subjects
X-ray powder diffraction ,METAL-organic frameworks ,THERMOGRAVIMETRY ,THERMAL stability ,POWDERS - Abstract
The employment of metal-organic frameworks in powder form is undesirable from an industrial perspective due to process and safety issues. This work is devoted to evaluating the impact of compression on the textural and structural properties of CPO-27(Ni). For this purpose, CPO-27(Ni) was synthesized under hydrosolvothermal conditions and characterized. Then, the resulting powder was compressed into binderless pellets using variable compression forces ranging from 5–90 kN (37–678 MPa) and characterized by means of nitrogen adsorption/desorption, thermogravimetric analysis and powder X-ray diffraction to evaluate textural, thermal and structural changes. Both textural and structural properties decreased with increasing compression force. Thermal stability was impacted in pellets compressed at forces over 70 kN. CPO-27(Ni) pelletized at 5, 8 and 10 kN, and retained more than 94% of its initial textural properties, while a loss of about one-third of the textural property was observed for the two most compressed samples (70 and 90 kN) compared to the starting powder. [ABSTRACT FROM AUTHOR]
- Published
- 2023
- Full Text
- View/download PDF
3. Dioxin and 1,2-dichlorobenzene adsorption in aluminosilicate zeolite Beta
- Author
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Bullot, Laetitia, Abda, Maher Ben, Simon-Masseron, Angélique, Jean Daou, T., Chaplais, Gérald, Nouali, Habiba, Schäf, Oliver, Zerega, Yves, Fiani, Emmanuel, and Patarin, Joël
- Published
- 2017
- Full Text
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4. The separation of xylene isomers by ZIF-8: A demonstration of the extraordinary flexibility of the ZIF-8 framework
- Author
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Peralta, David, Chaplais, Gérald, Paillaud, Jean-Louis, Simon-Masseron, Angélique, Barthelet, Karin, and Pirngruber, Gerhard D.
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SEPARATION (Technology) , *XYLENE , *ISOMERS , *ZEOLITES , *GAS phase reactions , *MOLECULAR sieves , *ETHYLBENZENE - Abstract
Abstract: The present work describes the adsorption and separation of xylene isomers by ZIF-8. Although the formal pore diameter of ZIF-8 is much smaller than the molecular diameter of the xylene isomers, ZIF-8 is able to separate the isomers by molecular sieving. A structural study indicates that the diffusion of the xylenes into the pore structure of ZIF-8 happens via a transitory deformation of the pore aperture which is based on a tilt of the imidazolate linkers, followed by a return to the initial conformation. The rate of adsorption depends on the size of the isomer, i.e. it decreases from para- to meta- and to ortho-xylene. The separation of the xylene isomers is good in the gas phase. In liquid phase breakthrough experiments, the quality of the separation is deteriorated. Moreover, as expected for a separation based on molecular sieving, para-xylene cannot be well separated from ethyl-benzene. [Copyright &y& Elsevier]
- Published
- 2013
- Full Text
- View/download PDF
5. Mechanism of water adsorption in the large pore form of the gallium-based MIL-53 metal-organic framework.
- Author
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Weber, Guy, Bezverkhyy, Igor, Bellat, Jean-Pierre, Ballandras, Anthony, Ortiz, Guillaume, Chaplais, Gérald, Patarin, Joël, Coudert, François-Xavier, Fuchs, Alain H., and Boutin, Anne
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ADSORPTION (Chemistry) , *GALLIUM , *ATMOSPHERIC temperature , *WATER research , *WATER pressure - Abstract
Water adsorption in the large pore ( lp_empty ) form of Ga-MIL-53 was studied by TGA, DSC and in situ XRD and FTIR at 298 K. The large pore form can be stabilized at room temperature after activation under vacuum at 553 K. The isotherm of water adsorption in this large pore form (pore dimensions: 1.67 × 1.33 nm) is very similar to that measured on the narrow pore ( np_empty ) form (pore dimensions: 1.97 × 0.76 nm). Such a similarity is rather unusual given that the pore sizes of these two phases are very different. In order to understand the origin of this effect in situ XRD and FTIR measurements were particularly helpful. It was found that the adsorption of even small amount of water (0.05 mol per Ga atom at 0.2 hPa) in the large pore form of Ga-MIL-53 transforms ca. 50% of the solid into a narrow pore int phase, which is assumed to be present as a shell around the lp_empty core. Additional water molecules adsorbed at higher pressures do not interact with the parent lp_empty phase but with the narrow pore int phase. The phase transformations were confirmed by FTIR revealing significant band displacements in the corresponding pressure ranges. Such easy pore shrinking which occurs at very low water pressure (<0.2 hPa) can have undesirable consequences in working conditions, as for example in separation adsorption processes, because the large pore structure of Ga-MIL-53 can be preserved only under anhydrous conditions. [ABSTRACT FROM AUTHOR]
- Published
- 2016
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6. An initial evaluation of the thermodynamic or kinetic separation performance of cation-exchanged LTA zeolites for mixtures of propane and propylene.
- Author
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Benchaabane, Mohammed-El Amine, Trierweiler Gonçalves, Gabriel, Bloch, Emily, Paillaud, Jean-Louis, Daou, T. Jean, Bourrelly, Sandrine, Chaplais, Gérald, and Llewellyn, Philip L.
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ZEOLITES , *GAS absorption & adsorption , *ADSORPTIVE separation , *ADSORPTION isotherms , *PROPENE , *PROPANE , *SEPARATION of gases - Abstract
Adsorptive separation of propylene (C 3 H 6) and propane (C 3 H 8) may represent an energy-efficient alternative to conventional cryogenic distillation. In this perspective, a set of zeolitic adsorbents of LTA type structure (pure-silica zeolite (Si-LTA) and cation- (Na+, 33% of Li+, 50% of Mg2+ and 50% of Ca2+) containing zeolites) were prepared, then characterized using various techniques such as PXRD, gas adsorption measurement, TGA, XRF, SEM and EDX mapping. Thanks to an in-house manometric dosing setup coupled with a Tian-Calvet type microcalorimeter, the pure gas adsorption isotherms and their corresponding differential enthalpies of adsorption were measured at 303 K and for pressures up to 5 bar. To fit those adsorption data, the dual-site Langmuir was selected as the best fit model, and by using the Ideal Adsorbed Solution Theory (IAST), thermodynamic selectivities were determined. The mass transfer constants were also estimated by fitting, separately, the Linear Driving Force (LDF) and isothermal micropore diffusion models to adsorption kinetic curves, thus allowing kinetic type selectivities to be calculated. The combination of those selectivities reveals that the thermodynamic separation of C 3 H 6 from C 3 H 8 is highly favorable on CaNa-LTA, followed by its MgNa-LTA counterpart with IAST selectivities around 15 and 5, respectively. On the other hand, the monovalent cationic zeolites (i.e., Na- and LiNa-LTA) show a predominance of steric effects. Also, except for Si-LTA which shows a moderate kinetic separation, the studied materials are potential candidates, in the following order CaNa- > MgNa- > LiNa- > Na-LTA, for the separation of C 3 H 6 from C 3 H 8 by adsorption-based technologies. [Display omitted] • Adsorption enthalpies of C3 on LTA zeolites have been measured by microcalorimetry. • LTA zeolite with Li+ and Na+ are able to kinetically separate C3 mixture. • LTA with Ca2+ and Mg2+ are promising candidates for thermodynamic separation. • Ca2+ cations effectively improve the IAST selectivity 3 times with respect to Mg2+. [ABSTRACT FROM AUTHOR]
- Published
- 2022
- Full Text
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7. Adsorption of CO2, CH4, and N2 on Zeolitic Imidazolate Frameworks: Experiments and Simulations
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Javier Pérez-Pellitero, Carlos Nieto-Draghi, Delphine Bazer-Bachi, Gérald Chaplais, David Peralta, Flor R. Siperstein, Hedi Amrouche, Angélique Simon-Masseron, Nicolas Bats, Gerhard D. Pirngruber, IFP Energies nouvelles (IFPEN), University of Manchester [Manchester], Institut de Science des Matériaux de Mulhouse (IS2M), Université de Haute-Alsace (UHA) Mulhouse - Colmar (Université de Haute-Alsace (UHA))-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS)-Matériaux et nanosciences d'Alsace (FMNGE), Institut de Chimie du CNRS (INC)-Université de Strasbourg (UNISTRA)-Université de Haute-Alsace (UHA) Mulhouse - Colmar (Université de Haute-Alsace (UHA))-Institut National de la Santé et de la Recherche Médicale (INSERM)-Centre National de la Recherche Scientifique (CNRS)-Université de Strasbourg (UNISTRA)-Institut National de la Santé et de la Recherche Médicale (INSERM)-Centre National de la Recherche Scientifique (CNRS)-Réseau nanophotonique et optique, Centre National de la Recherche Scientifique (CNRS)-Université de Strasbourg (UNISTRA)-Université de Haute-Alsace (UHA) Mulhouse - Colmar (Université de Haute-Alsace (UHA))-Centre National de la Recherche Scientifique (CNRS)-Université de Strasbourg (UNISTRA), CHAPLAIS, Gérald, Université de Haute-Alsace (UHA) Mulhouse - Colmar (Université de Haute-Alsace (UHA))-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS)-Matériaux et Nanosciences Grand-Est (MNGE), Université de Strasbourg (UNISTRA)-Université de Haute-Alsace (UHA) Mulhouse - Colmar (Université de Haute-Alsace (UHA))-Institut National de la Santé et de la Recherche Médicale (INSERM)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS)-Université de Strasbourg (UNISTRA)-Institut National de la Santé et de la Recherche Médicale (INSERM)-Centre National de la Recherche Scientifique (CNRS)-Réseau nanophotonique et optique, and Université de Strasbourg (UNISTRA)-Université de Haute-Alsace (UHA) Mulhouse - Colmar (Université de Haute-Alsace (UHA))-Centre National de la Recherche Scientifique (CNRS)-Université de Strasbourg (UNISTRA)-Centre National de la Recherche Scientifique (CNRS)
- Subjects
Chemistry ,Organic Chemistry ,Inorganic chemistry ,Molecular simulation ,02 engineering and technology ,General Chemistry ,010402 general chemistry ,021001 nanoscience & nanotechnology ,01 natural sciences ,Catalysis ,Force field (chemistry) ,0104 chemical sciences ,Metal ,Adsorption ,Preferential adsorption ,Chemical physics ,visual_art ,[CHIM] Chemical Sciences ,visual_art.visual_art_medium ,[CHIM]Chemical Sciences ,Metal-organic framework ,Topological mapping ,0210 nano-technology ,Zeolitic imidazolate framework - Abstract
International audience; Experimental measurements and molecular simulations were conducted for two zeolitic imidazolate frameworks, ZIF‐8 and ZIF‐76. The transferability of the force field was tested by comparing molecular simulation results of gas adsorption with experimental data available in the literature for other ZIF materials (ZIF‐69). Owing to the good agreement observed between simulation and experimental data, the simulation results can be used to identify preferential adsorption sites, which are located close to the organic linkers. Topological mapping of the potential‐energy surfaces makes it possible to relate the preferential adsorption sites, Henry constant, and isosteric heats of adsorption at zero coverage to the nature of the host–guest interactions and the chemical nature of the organic linker. The role played by the topology of the solid and the organic linkers, instead of the metal sites, upon gas adsorption on zeolite‐like metal–organic frameworks is discussed.
- Published
- 2010
Catalog
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