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Li C, Zhang Z, Heinke L. Mass transfer of toluene in a series of metal-organic frameworks: molecular clusters inside the nanopores cause slow and step-like release. Phys Chem Chem Phys 2022; 24:3994-4001. [PMID: 35103267 DOI: 10.1039/d1cp05560g] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
Abstract
The mass transfer of the guest molecules in the pores is fundamental for the application of nanoporous materials like metal-organic frameworks, MOFs. In the present work, we explore the uptake and release of toluene in a series of Zr-based MOFs with different pore sizes. We find that intermolecular guest-guest interaction, sterically controlled by the pore size, has a substantial impact on the release kinetics. While the adsorption is rather fast, the desorption process is many orders of magnitude slower. Depending on the pore size, molecular clusters form, here (most likely) toluene dimers, which are rather stable and their break-up is rate-limiting during the desorption process. This results in a step-like desorption kinetics, deviating from the plain Fickian-diffusion-controlled release. Temperature-dependent experiments show that the minimum and maximum of the release rates are obtained at the same toluene loadings, independent of the temperature. Moreover, the activation energy for the release coincides with the binding energy of a toluene dimer. The work shows the importance of intermolecular guest-guest interaction, controlled by the MOF-nanoconfinement, for the uptake and release from nanoporous materials.
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Affiliation(s)
- Chun Li
- Institute of Functional Interfaces (IFG), Karlsruhe Institute of Technology (KIT), Hermann-von-Helmholtz-Platz 1, 76344 Eggenstein-Leopoldshafen, Germany.
| | - Zejun Zhang
- Institute of Functional Interfaces (IFG), Karlsruhe Institute of Technology (KIT), Hermann-von-Helmholtz-Platz 1, 76344 Eggenstein-Leopoldshafen, Germany.
| | - Lars Heinke
- Institute of Functional Interfaces (IFG), Karlsruhe Institute of Technology (KIT), Hermann-von-Helmholtz-Platz 1, 76344 Eggenstein-Leopoldshafen, Germany.
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2
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Krishna R, van Baten JM. How Reliable Is the Ideal Adsorbed Solution Theory for the Estimation of Mixture Separation Selectivities in Microporous Crystalline Adsorbents? ACS OMEGA 2021; 6:15499-15513. [PMID: 34151128 PMCID: PMC8210411 DOI: 10.1021/acsomega.1c02136] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 04/22/2021] [Accepted: 05/25/2021] [Indexed: 06/13/2023]
Abstract
Microporous crystalline adsorbents such as zeolites and metal-organic frameworks (MOFs) have potential use in a wide variety of separation applications. The adsorption selectivity S ads is a key metric that quantifies the efficacy of any microporous adsorbent in mixture separations. The Ideal Adsorbed Solution Theory (IAST) is commonly used for estimating the value of S ads, with unary isotherms of the constituent guests as data inputs. There are two basic tenets underlying the development of the IAST. The first tenet mandates a homogeneous distribution of adsorbates within the pore landscape. The second tenet requires the surface area occupied by a guest molecule in the mixture to be the same as that for the corresponding pure component. Configurational-bias Monte Carlo (CBMC) simulations are employed in this article to highlight several scenarios in which the IAST fails to provide a quantitatively correct description of mixture adsorption equilibrium due to a failure to conform to either of the two tenets underpinning the IAST. For CO2 capture with cation-exchanged zeolites and MOFs with open metal sites, there is congregation of CO2 around the cations and unsaturated metal atoms, resulting in failure of the IAST due to an inhomogeneous distribution of adsorbates in the pore space. Thermodynamic non-idealities also arise due to the preferential location of CO2 molecules at the window regions of 8-ring zeolites such as DDR and CHA or within pockets of MOR and AFX zeolites. Thermodynamic non-idealities are evidenced for water/alcohol mixtures due to molecular clustering engendered by hydrogen bonding. It is also demonstrated that thermodynamic non-idealities can be strong enough to cause selectivity reversals, which are not anticipated by the IAST.
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Affiliation(s)
- Mohammad I. Hossain
- Department of Chemical and Biomolecular Engineering, University of South Alabama, Mobile, Alabama 36677, United States
| | - T. Grant Glover
- Department of Chemical and Biomolecular Engineering, University of South Alabama, Mobile, Alabama 36677, United States
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DeJaco RF, Elyassi B, Dorneles de Mello M, Mittal N, Tsapatsis M, Siepmann JI. Understanding the unique sorption of alkane-α, ω-diols in silicalite-1. J Chem Phys 2018; 149:072331. [DOI: 10.1063/1.5026937] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Affiliation(s)
- Robert F. DeJaco
- Department of Chemical Engineering and Materials Science, University of Minnesota, 412 Washington Avenue SE, Minneapolis, Minnesota 55455-0132, USA
- Department of Chemistry and Chemical Theory Center, University of Minnesota, 207 Pleasant Street SE, Minneapolis, Minnesota 55455-0431, USA
| | - Bahman Elyassi
- Department of Chemical Engineering and Materials Science, University of Minnesota, 412 Washington Avenue SE, Minneapolis, Minnesota 55455-0132, USA
| | - Matheus Dorneles de Mello
- Department of Chemical Engineering and Materials Science, University of Minnesota, 412 Washington Avenue SE, Minneapolis, Minnesota 55455-0132, USA
| | - Nitish Mittal
- Department of Chemical Engineering and Materials Science, University of Minnesota, 412 Washington Avenue SE, Minneapolis, Minnesota 55455-0132, USA
| | - Michael Tsapatsis
- Department of Chemical Engineering and Materials Science, University of Minnesota, 412 Washington Avenue SE, Minneapolis, Minnesota 55455-0132, USA
| | - J. Ilja Siepmann
- Department of Chemical Engineering and Materials Science, University of Minnesota, 412 Washington Avenue SE, Minneapolis, Minnesota 55455-0132, USA
- Department of Chemistry and Chemical Theory Center, University of Minnesota, 207 Pleasant Street SE, Minneapolis, Minnesota 55455-0431, USA
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6
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Liu Y, Meng Z, Guo X, Xu G, Rao D, Wang Y, Deng K, Lu R. Ca-Embedded C 2N: an efficient adsorbent for CO 2 capture. Phys Chem Chem Phys 2018; 19:28323-28329. [PMID: 29034383 DOI: 10.1039/c7cp05325h] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Carbon dioxide as a greenhouse gas causes severe impacts on the environment, whereas it is also a necessary chemical feedstock that can be converted into carbon-based fuels via electrochemical reduction. To efficiently and reversibly capture CO2, it is important to find novel materials for a good balance between adsorption and desorption. In this study, we performed first-principles calculations and grand canonical Monte Carlo (GCMC) simulations, to systematically study metal-embedded carbon nitride (C2N) nanosheets for CO2 capture. Our first-principles results indicated that Ca atoms can be uniformly trapped in the cavity center of C2N structure, while the transition metals (Sc, Ti, V, Cr, Mn, Fe, Co) are favorably embedded in the sites off the center of the cavity. The determined maximum number of CO2 molecules with strong physisorption showed that Ca-embedded C2N monolayer is the most promising CO2 adsorbent among all considered metal-embedded materials. Moreover, GCMC simulations revealed that at room temperature the gravimetric density for CO2 adsorbed on Ca-embedded C2N reached 50 wt% at 30 bar and 23 wt% at 1 bar, higher than other layered materials, thus providing a satisfactory system for the CO2 capture and utilization.
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Affiliation(s)
- Yuzhen Liu
- Department of Applied Physics, Nanjing University of Science and Technology, Nanjing 210094, People's Republic of China.
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Lu Y, Lucier BEG, Zhang Y, Ren P, Zheng A, Huang Y. Sizable dynamics in small pores: CO 2 location and motion in the α-Mg formate metal-organic framework. Phys Chem Chem Phys 2018; 19:6130-6141. [PMID: 28191584 DOI: 10.1039/c7cp00199a] [Citation(s) in RCA: 29] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Metal-organic frameworks (MOFs) are promising materials for carbon dioxide (CO2) adsorption and storage; however, many details regarding CO2 dynamics and specific adsorption site locations within MOFs remain unknown, restricting the practical uses of MOFs for CO2 capture. The intriguing α-magnesium formate (α-Mg3(HCOO)6) MOF can adsorb CO2 and features a small pore size. Using an intertwined approach of 13C solid-state NMR (SSNMR) spectroscopy, 1H-13C cross-polarization SSNMR, and computational molecular dynamics (MD) simulations, new physical insights and a rich variety of information have been uncovered regarding CO2 adsorption in this MOF, including the surprising suggestion that CO2 motion is restricted at elevated temperatures. Guest CO2 molecules undergo a combined localized rotational wobbling and non-localized twofold jumping between adsorption sites. MD simulations and SSNMR experiments accurately locate the CO2 adsorption sites; the mechanism behind CO2 adsorption is the distant interaction between the hydrogen atom of the MOF formate linker and a guest CO2 oxygen atom, which are ca. 3.2 Å apart.
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Affiliation(s)
- Yuanjun Lu
- Department of Chemistry, The University of Western Ontario, 1151 Richmond Street, London, Ontario N6A 5B7, Canada.
| | - Bryan E G Lucier
- Department of Chemistry, The University of Western Ontario, 1151 Richmond Street, London, Ontario N6A 5B7, Canada.
| | - Yue Zhang
- Department of Chemistry, The University of Western Ontario, 1151 Richmond Street, London, Ontario N6A 5B7, Canada.
| | - Pengju Ren
- State Key Laboratory of Coal Conversion, Institute of Coal Chemistry, Chinese Academy of Sciences, Taiyuan, 030001, P. R. China and National Energy Center for Coal to Clean Fuels, Synfuels China Co., Ltd, Huairou District, Beijing, 101400, P. R. China
| | - Anmin Zheng
- State Key Laboratory of Magnetic Resonance and Atomic and Molecular Physics, Wuhan Center for Magnetic Resonance, Wuhan Institute of Physics and Mathematics, the Chinese Academy of Sciences, Wuhan 430071, P. R. China
| | - Yining Huang
- Department of Chemistry, The University of Western Ontario, 1151 Richmond Street, London, Ontario N6A 5B7, Canada.
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Pillai RS, Jobic H, Koza MM, Nouar F, Serre C, Maurin G, Ramsahye NA. Diffusion of Carbon Dioxide and Nitrogen in the Small‐Pore Titanium Bis(phosphonate) Metal–Organic Framework MIL‐91 (Ti): A Combination of Quasielastic Neutron Scattering Measurements and Molecular Dynamics Simulations. Chemphyschem 2017; 18:2739-2746. [DOI: 10.1002/cphc.201700459] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/28/2017] [Revised: 06/12/2017] [Indexed: 11/10/2022]
Affiliation(s)
- Renjith Sasimohanan Pillai
- Institut Charles Gerhardt Montpellier, UMR-5253Université de Montpellier, CNRS, ENSCM Place E. Bataillon Montpellier cedex 05 34095 France
| | - Hervé Jobic
- Institut de Recherches sur la Catalyse et l'Environnement de Lyon, CNRSUniversité de Lyon 2. Av. A. Einstein 69626 Villeurbanne France
| | | | - Farid Nouar
- Paris Res UnivEcole Super Phys & Chim Ind Paris, Ecole Normale Super, Inst Mat Poreux Paris, FRE CNRS 2000 Paris France
| | - Christian Serre
- Paris Res UnivEcole Super Phys & Chim Ind Paris, Ecole Normale Super, Inst Mat Poreux Paris, FRE CNRS 2000 Paris France
| | - Guillaume Maurin
- Institut Charles Gerhardt Montpellier, UMR-5253Université de Montpellier, CNRS, ENSCM Place E. Bataillon Montpellier cedex 05 34095 France
| | - Naseem Ahmed Ramsahye
- Institut Charles Gerhardt Montpellier, UMR-5253Université de Montpellier, CNRS, ENSCM Place E. Bataillon Montpellier cedex 05 34095 France
- Institut Charles Gerhardt Montpellier, UMR-525Université de Montpellier, CNRS, ENSCM Institution 8 rue de l'Ecole Normale, cedex 05 34296 France
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Braun E, Chen JJ, Schnell SK, Lin LC, Reimer JA, Smit B. Nanoporous Materials Can Tune the Critical Point of a Pure Substance. Angew Chem Int Ed Engl 2015; 54:14349-52. [PMID: 26419318 PMCID: PMC4678509 DOI: 10.1002/anie.201506865] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/27/2015] [Indexed: 11/07/2022]
Abstract
Molecular simulations and NMR relaxometry experiments demonstrate that pure benzene or xylene confined in isoreticular metal–organic frameworks (IRMOFs) exhibit true vapor–liquid phase equilibria where the effective critical point may be reduced by tuning the structure of the MOF. Our results are consistent with vapor and liquid phases extending over many MOF unit cells. These results are counterintuitive since the MOF pore diameters are approximately the same length scale as the adsorbate molecules. As applications of these materials in catalysis, separations, and gas storage rely on the ability to tune the properties of adsorbed molecules, we anticipate that the ability to systematically control the critical point, thereby preparing spatially inhomogeneous local adsorbate densities, could add a new design tool for MOF applications.
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Affiliation(s)
- Efrem Braun
- Department of Chemical and Biomolecular Engineering, University of California, Berkeley, Berkeley, CA 94720 (USA)
| | - Joseph J Chen
- Department of Chemical and Biomolecular Engineering, University of California, Berkeley, Berkeley, CA 94720 (USA)
| | - Sondre K Schnell
- Department of Chemical and Biomolecular Engineering, University of California, Berkeley, Berkeley, CA 94720 (USA).,Department of Chemistry, Norwegian University of Science and Technology, 7491 Trondheim (Norway)
| | - Li-Chiang Lin
- Department of Chemical and Biomolecular Engineering, University of California, Berkeley, Berkeley, CA 94720 (USA).,Department of Process and Energy, Delft University of Technology, Leeghwaterstraat 39, 2628 CB Delft (The Netherlands)
| | - Jeffrey A Reimer
- Department of Chemical and Biomolecular Engineering, University of California, Berkeley, Berkeley, CA 94720 (USA). .,Materials Science Division, Lawrence Berkeley National Laboratory, 1 Cyclotron Road, Berkeley, CA 94720 (USA).
| | - Berend Smit
- Department of Chemical and Biomolecular Engineering, University of California, Berkeley, Berkeley, CA 94720 (USA). .,Materials Science Division, Lawrence Berkeley National Laboratory, 1 Cyclotron Road, Berkeley, CA 94720 (USA). .,Department of Chemistry, University of California, Berkeley, Berkeley, CA 94720 (USA). .,Institut des Sciences et Ingénierie Chimiques (ISIC), Valais, Ecole Polytechnique Fédérale de Lausanne (EPFL), Rue de l'Industrie 17, CH-1951 Sion (Switzerland).
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10
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Braun E, Chen JJ, Schnell SK, Lin L, Reimer JA, Smit B. Nanoporous Materials Can Tune the Critical Point of a Pure Substance. Angew Chem Int Ed Engl 2015. [DOI: 10.1002/ange.201506865] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Affiliation(s)
- Efrem Braun
- Department of Chemical and Biomolecular Engineering, University of California, Berkeley, Berkeley, CA 94720 (USA)
| | - Joseph J. Chen
- Department of Chemical and Biomolecular Engineering, University of California, Berkeley, Berkeley, CA 94720 (USA)
| | - Sondre K. Schnell
- Department of Chemical and Biomolecular Engineering, University of California, Berkeley, Berkeley, CA 94720 (USA)
- Department of Chemistry, Norwegian University of Science and Technology, 7491 Trondheim (Norway)
| | - Li‐Chiang Lin
- Department of Chemical and Biomolecular Engineering, University of California, Berkeley, Berkeley, CA 94720 (USA)
- Department of Process and Energy, Delft University of Technology, Leeghwaterstraat 39, 2628 CB Delft (The Netherlands)
| | - Jeffrey A. Reimer
- Department of Chemical and Biomolecular Engineering, University of California, Berkeley, Berkeley, CA 94720 (USA)
- Materials Science Division, Lawrence Berkeley National Laboratory, 1 Cyclotron Road, Berkeley, CA 94720 (USA)
| | - Berend Smit
- Department of Chemical and Biomolecular Engineering, University of California, Berkeley, Berkeley, CA 94720 (USA)
- Materials Science Division, Lawrence Berkeley National Laboratory, 1 Cyclotron Road, Berkeley, CA 94720 (USA)
- Department of Chemistry, University of California, Berkeley, Berkeley, CA 94720 (USA)
- Institut des Sciences et Ingénierie Chimiques (ISIC), Valais, Ecole Polytechnique Fédérale de Lausanne (EPFL), Rue de l'Industrie 17, CH‐1951 Sion (Switzerland)
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11
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Gutiérrez-Sevillano JJ, Calero S, Krishna R. Separation of benzene from mixtures with water, methanol, ethanol, and acetone: highlighting hydrogen bonding and molecular clustering influences in CuBTC. Phys Chem Chem Phys 2015; 17:20114-24. [PMID: 26165859 DOI: 10.1039/c5cp02726h] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Configurational-bias Monte Carlo (CBMC) simulations are used to establish the potential of CuBTC for separation of water/benzene, methanol/benzene, ethanol/benzene, and acetone/benzene mixtures. For operations under pore saturation conditions, the separations are in favor of molecules that partner benzene; this is due to molecular packing effects that disfavor benzene. CBMC simulations for adsorption of quaternary water/methanol/ethanol/benzene mixtures show that water can be selectively adsorbed at pore saturation, making CuBTC effective in drying applications. Ideal Adsorbed Solution Theory (IAST) calculations anticipate the right hierarchy of component loadings but the quantitative agreement with CBMC mixture simulations is poor for all investigated mixtures. The failure of the IAST to provide reasonable quantitative predictions of mixture adsorption is attributable to molecular clustering effects that are induced by hydrogen bonding between water-water, methanol-methanol, and ethanol-ethanol molecule pairs. There is, however, no detectable hydrogen bonding between benzene and partner molecules in the investigated mixtures. As a consequence of molecular clustering, the activity coefficients of benzene in the mixtures is lowered below unity by one to three orders of magnitude at pore saturation; such drastic reductions cannot be adequately captured by the Wilson model, that does not explicitly account for molecular clustering. Molecular clustering effects are also shown to influence the loading dependence of the diffusivities of guest molecules.
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Affiliation(s)
- Juan José Gutiérrez-Sevillano
- Department of Physical, Chemical and Natural Systems, University Pablo de Olavide, Ctra. Utrera km 1, 41013 Sevilla, Spain.
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Yang Y, Sitprasert C, Rufford TE, Ge L, Shukla P, Wang S, Rudolph V, Zhu Z. An experimental and simulation study of binary adsorption in metal–organic frameworks. Sep Purif Technol 2015. [DOI: 10.1016/j.seppur.2015.03.041] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
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13
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Krishna R. Evaluation of procedures for estimation of the isosteric heat of adsorption in microporous materials. Chem Eng Sci 2015. [DOI: 10.1016/j.ces.2014.11.007] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
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14
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Magdysyuk OV, Denysenko D, Weinrauch I, Volkmer D, Hirscher M, Dinnebier RE. Formation of a quasi-solid structure by intercalated noble gas atoms in pores of CuI-MFU-4l metal–organic framework. Chem Commun (Camb) 2015; 51:714-7. [DOI: 10.1039/c4cc07554d] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/23/2023]
Abstract
Ten crystallographically different positions for Xe and eight positions for Kr form a quasi-solid structures within the large-pore metal–organic framework CuI-MFU-4l.
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Affiliation(s)
| | - Dmytro Denysenko
- Augsburg University
- Institute of Physics
- Chair of Solid State and Materials Chemistry
- Augsburg
- Germany
| | | | - Dirk Volkmer
- Augsburg University
- Institute of Physics
- Chair of Solid State and Materials Chemistry
- Augsburg
- Germany
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15
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Yu N, Wang L, Li M, Sun X, Hou T, Li Y. Molybdenum disulfide as a highly efficient adsorbent for non-polar gases. Phys Chem Chem Phys 2015; 17:11700-4. [DOI: 10.1039/c5cp00161g] [Citation(s) in RCA: 64] [Impact Index Per Article: 7.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Molybdenum disulfide with vacancies is predicted to be an efficient absorbent for CO2 and CH4 molecules, and the gravimetric adsorption can be as high as 42 wt%.
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Affiliation(s)
- Ningning Yu
- Functional Nano & Soft Materials Laboratory (FUNSOM)
- Soochow University
- Suzhou
- China
| | - Lu Wang
- Functional Nano & Soft Materials Laboratory (FUNSOM)
- Soochow University
- Suzhou
- China
| | - Min Li
- Functional Nano & Soft Materials Laboratory (FUNSOM)
- Soochow University
- Suzhou
- China
| | - Xiaotian Sun
- Functional Nano & Soft Materials Laboratory (FUNSOM)
- Soochow University
- Suzhou
- China
| | - Tingjun Hou
- Functional Nano & Soft Materials Laboratory (FUNSOM)
- Soochow University
- Suzhou
- China
| | - Youyong Li
- Functional Nano & Soft Materials Laboratory (FUNSOM)
- Soochow University
- Suzhou
- China
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16
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Becker T, Nelissen K, Cleuren B, Partoens B, Van den Broeck C. Diffusion of interacting particles in discrete geometries: Equilibrium and dynamical properties. PHYSICAL REVIEW. E, STATISTICAL, NONLINEAR, AND SOFT MATTER PHYSICS 2014; 90:052139. [PMID: 25493771 DOI: 10.1103/physreve.90.052139] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/13/2014] [Indexed: 06/04/2023]
Abstract
We expand on a recent study of a lattice model of interacting particles [Phys. Rev. Lett. 111, 110601 (2013)PRLTAO0031-900710.1103/PhysRevLett.111.110601]. The adsorption isotherm and equilibrium fluctuations in particle number are discussed as a function of the interaction. Their behavior is similar to that of interacting particles in porous materials. Different expressions for the particle jump rates are derived from transition-state theory. Which expression should be used depends on the strength of the interparticle interactions. Analytical expressions for the self- and transport diffusion are derived when correlations, caused by memory effects in the environment, are neglected. The diffusive behavior is studied numerically with kinetic Monte Carlo (kMC) simulations, which reproduces the diffusion including correlations. The effect of correlations is studied by comparing the analytical expressions with the kMC simulations. It is found that the Maxwell-Stefan diffusion can exceed the self-diffusion. To our knowledge, this is the first time this is observed. The diffusive behavior in one-dimensional and higher-dimensional systems is qualitatively the same, with the effect of correlations decreasing for increasing dimension. The length dependence of both the self- and transport diffusion is studied for one-dimensional systems. For long lengths the self-diffusion shows a 1/L dependence. Finally, we discuss when agreement with experiments and simulations can be expected. The assumption that particles in different cavities do not interact is expected to hold quantitatively at low and medium particle concentrations if the particles are not strongly interacting.
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Affiliation(s)
- T Becker
- Hasselt University, B-3590 Diepenbeek, Belgium
| | - K Nelissen
- Hasselt University, B-3590 Diepenbeek, Belgium and Departement Fysica, Universiteit Antwerpen, Groenenborgerlaan 171, B-2020 Antwerpen, Belgium
| | - B Cleuren
- Hasselt University, B-3590 Diepenbeek, Belgium
| | - B Partoens
- Departement Fysica, Universiteit Antwerpen, Groenenborgerlaan 171, B-2020 Antwerpen, Belgium
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17
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Lito PF, Cardoso SP, Rodrigues AE, Silva CM. Kinetic Modeling of Pure and Multicomponent Gas Permeation Through Microporous Membranes: Diffusion Mechanisms and Influence of Isotherm Type. SEPARATION AND PURIFICATION REVIEWS 2014. [DOI: 10.1080/15422119.2014.908918] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
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18
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Van Speybroeck V, De Wispelaere K, Van der Mynsbrugge J, Vandichel M, Hemelsoet K, Waroquier M. First principle chemical kinetics in zeolites: the methanol-to-olefin process as a case study. Chem Soc Rev 2014; 43:7326-57. [PMID: 25054453 DOI: 10.1039/c4cs00146j] [Citation(s) in RCA: 135] [Impact Index Per Article: 13.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Abstract
To optimally design next generation catalysts a thorough understanding of the chemical phenomena at the molecular scale is a prerequisite. Apart from qualitative knowledge on the reaction mechanism, it is also essential to be able to predict accurate rate constants. Molecular modeling has become a ubiquitous tool within the field of heterogeneous catalysis. Herein, we review current computational procedures to determine chemical kinetics from first principles, thus by using no experimental input and by modeling the catalyst and reacting species at the molecular level. Therefore, we use the methanol-to-olefin (MTO) process as a case study to illustrate the various theoretical concepts. This process is a showcase example where rational design of the catalyst was for a long time performed on the basis of trial and error, due to insufficient knowledge of the mechanism. For theoreticians the MTO process is particularly challenging as the catalyst has an inherent supramolecular nature, for which not only the Brønsted acidic site is important but also organic species, trapped in the zeolite pores, must be essentially present during active catalyst operation. All these aspects give rise to specific challenges for theoretical modeling. It is shown that present computational techniques have matured to a level where accurate enthalpy barriers and rate constants can be predicted for reactions occurring at a single active site. The comparison with experimental data such as apparent kinetic data for well-defined elementary reactions has become feasible as current computational techniques also allow predicting adsorption enthalpies with reasonable accuracy. Real catalysts are truly heterogeneous in a space- and time-like manner. Future theory developments should focus on extending our view towards phenomena occurring at longer length and time scales and integrating information from various scales towards a unified understanding of the catalyst. Within this respect molecular dynamics methods complemented with additional techniques to simulate rare events are now gradually making their entrance within zeolite catalysis. Recent applications have already given a flavor of the benefit of such techniques to simulate chemical reactions in complex molecular environments.
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Pera-Titus M. Porous inorganic membranes for CO2 capture: present and prospects. Chem Rev 2013; 114:1413-92. [PMID: 24299113 DOI: 10.1021/cr400237k] [Citation(s) in RCA: 282] [Impact Index Per Article: 25.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Affiliation(s)
- Marc Pera-Titus
- Institut de Recherches sur la Catalyse et l'Environnement de Lyon (IRCELYON), Université de Lyon, UMR 5256 CNRS-Université Lyon 1 , 2 Av. A. Einstein, 69626 Villeurbanne Cedex, France
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20
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Becker T, Nelissen K, Cleuren B, Partoens B, Van den Broeck C. Diffusion of interacting particles in discrete geometries. PHYSICAL REVIEW LETTERS 2013; 111:110601. [PMID: 24074065 DOI: 10.1103/physrevlett.111.110601] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/03/2013] [Indexed: 06/02/2023]
Abstract
We evaluate the self-diffusion and transport diffusion of interacting particles in a discrete geometry consisting of a linear chain of cavities, with interactions within a cavity described by a free-energy function. Exact analytical expressions are obtained in the absence of correlations, showing that the self-diffusion can exceed the transport diffusion if the free-energy function is concave. The effect of correlations is elucidated by comparison with numerical results. Quantitative agreement is obtained with recent experimental data for diffusion in a nanoporous zeolitic imidazolate framework material, ZIF-8.
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Affiliation(s)
- T Becker
- Hasselt University, B-3590 Diepenbeek, Belgium
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Krishna R, van Baten JM. Influence of adsorption thermodynamics on guest diffusivities in nanoporous crystalline materials. Phys Chem Chem Phys 2013; 15:7994-8016. [PMID: 23628965 DOI: 10.1039/c3cp50449b] [Citation(s) in RCA: 61] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/23/2023]
Abstract
Published experimental data, underpinned by molecular simulations, are used to highlight the strong influence of adsorption thermodynamics on diffusivities of guest molecules inside ordered nanoporous crystalline materials such as zeolites, metal-organic frameworks (MOFs), and zeolitic imidazolate frameworks (ZIFs). For cage-type structures (e.g. LTA, CHA, DDR, and ZIF-8), the variation of the free energy barrier for inter-cage hopping across the narrow windows, -δFi, provides a rationalization of the observed strong influence of pore concentrations, ci, on diffusivities. In open structures with large pore volumes (e.g. FAU, IRMOF-1, CuBTC) and within channels (MFI, BEA, MgMOF-74, MIL-47, MIL-53), the pore concentration (ci) dependence of the self- (Di,self), Maxwell-Stefan (Đi), and Fick (Di) diffusivities are often strongly dictated by the inverse thermodynamic correction factor, 1/Γi≡∂ln ci/∂ln pi; the magnitudes of the diffusivities are dictated by the binding energies for adsorption. For many guest-host combinations Đi-ci dependence is directly related to the 1/Γivs. ci variation. When molecular clustering occurs, we get 1/Γi > 1, causing unusual Đivs. ci dependencies. The match, or mis-match, between the periodicity of the pore landscape and the conformations of adsorbed chain molecules often leads to non-monotonic variation of diffusivities with chain lengths.
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Affiliation(s)
- Rajamani Krishna
- Van't Hoff Institute for Molecular Sciences, University of Amsterdam, Science Park 904, 1098 XH Amsterdam, The Netherlands.
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Tsotsalas M, Hejcik P, Sumida K, Kalay Z, Furukawa S, Kitagawa S. Impact of Molecular Clustering inside Nanopores on Desorption Processes. J Am Chem Soc 2013; 135:4608-11. [DOI: 10.1021/ja312115x] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
Affiliation(s)
- Manuel Tsotsalas
- Institute for Integrated Cell-Material
Sciences (WPI-iCeMS), Kyoto University,
Yoshida, Sakyo-ku, Kyoto 606-8501, Japan
- ERATO Kitagawa Integrated Pores
Project, Japan Science and Technology Agency, Kyoto Research Park Bldg #3, Shimogyo-ku, Kyoto 600-8815, Japan
| | - Pavel Hejcik
- Institute for Integrated Cell-Material
Sciences (WPI-iCeMS), Kyoto University,
Yoshida, Sakyo-ku, Kyoto 606-8501, Japan
| | - Kenji Sumida
- Institute for Integrated Cell-Material
Sciences (WPI-iCeMS), Kyoto University,
Yoshida, Sakyo-ku, Kyoto 606-8501, Japan
| | - Ziya Kalay
- Institute for Integrated Cell-Material
Sciences (WPI-iCeMS), Kyoto University,
Yoshida, Sakyo-ku, Kyoto 606-8501, Japan
| | - Shuhei Furukawa
- Institute for Integrated Cell-Material
Sciences (WPI-iCeMS), Kyoto University,
Yoshida, Sakyo-ku, Kyoto 606-8501, Japan
- ERATO Kitagawa Integrated Pores
Project, Japan Science and Technology Agency, Kyoto Research Park Bldg #3, Shimogyo-ku, Kyoto 600-8815, Japan
| | - Susumu Kitagawa
- Institute for Integrated Cell-Material
Sciences (WPI-iCeMS), Kyoto University,
Yoshida, Sakyo-ku, Kyoto 606-8501, Japan
- ERATO Kitagawa Integrated Pores
Project, Japan Science and Technology Agency, Kyoto Research Park Bldg #3, Shimogyo-ku, Kyoto 600-8815, Japan
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23
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Investigating the influence of diffusional coupling on mixture permeation across porous membranes. J Memb Sci 2013. [DOI: 10.1016/j.memsci.2012.12.004] [Citation(s) in RCA: 41] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
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24
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Zhang Y, Li B, Williams K, Gao WY, Ma S. A new microporous carbon material synthesized via thermolysis of a porous aromatic framework embedded with an extra carbon source for low-pressure CO2 uptake. Chem Commun (Camb) 2013; 49:10269-71. [DOI: 10.1039/c3cc45252b] [Citation(s) in RCA: 70] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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25
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X-Nuclei NMR Self-Diffusion Studies in Mesoporous Silica Foam and Microporous MOF CuBTC. MATERIALS 2012; 5:617-633. [PMID: 28816999 PMCID: PMC5448958 DOI: 10.3390/ma5040617] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 02/21/2012] [Revised: 03/30/2012] [Accepted: 04/01/2012] [Indexed: 11/17/2022]
Abstract
A standard X-observe NMR probe was equipped with a z-gradient coil to enable high-sensitivity pulsed field gradient NMR diffusion studies of Li+ and Cs+ cations of aqueous salt solutions in a high-porosity mesocellular silica foam (MCF) and of CO2 adsorbed in metal-organic frameworks (MOF). The coil design and the necessary probe modifications, which yield pulsed field gradients of up to ±16.2Tm-1, are introduced. The system was calibrated at 2H resonance frequency and successfully applied for diffusion studies at 7Li, 23Na, 13C and 133Cs frequencies. Significant reductions of the diffusivities of the cations in LiClac and CsClac solution introduced into MCFs are observed. By comparison of the diffusion behavior with the bulk solutions, a tortuosity of the silica foam of 4.5±0.6 was derived. Single component self-diffusion of CO2 and CH4 (measured by 1H NMR) as well as self-diffusion of the individual components in CO2/CH4 mixtures was studied in the MOF CuBTC. The experimental results confirm high mobilities of the adsorbed gases and trends for diffusion separation factors predicted by MD simulations.
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31
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Billemont P, Coasne B, De Weireld G. An experimental and molecular simulation study of the adsorption of carbon dioxide and methane in nanoporous carbons in the presence of water. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2011; 27:1015-1024. [PMID: 21190347 DOI: 10.1021/la103107t] [Citation(s) in RCA: 31] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/30/2023]
Abstract
The adsorption of carbon dioxide and methane in nanoporous carbons in the presence of water is studied using experiments and molecular simulations. For all amounts of adsorbed water molecules, the adsorption isotherms for carbon dioxide and methane resemble those obtained for pure fluids. The pore filling mechanism does not seem to be affected by the presence of the water molecules. Moreover, the pressure at which the maximum adsorbed amount of methane or carbon dioxide is reached is nearly insensitive to the loading of preadsorbed water molecules. In contrast, the adsorbed amount of methane or carbon dioxide decreases linearly with the number of guest water molecules. Typical molecular configurations obtained using molecular simulation indicate that the water molecules form isolated clusters within the host porous carbon due to the nonfavorable interaction between carbon dioxide or methane and water.
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Affiliation(s)
- Pierre Billemont
- Thermodynamics Department, Faculté Polytechnique, UMons, Université de Mons, 20 place du Parc, 70000 Mons, Belgium
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32
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Meek ST, Greathouse JA, Allendorf MD. Metal-organic frameworks: a rapidly growing class of versatile nanoporous materials. ADVANCED MATERIALS (DEERFIELD BEACH, FLA.) 2011; 23:249-67. [PMID: 20972981 DOI: 10.1002/adma.201002854] [Citation(s) in RCA: 785] [Impact Index Per Article: 60.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/21/2023]
Abstract
Metal-organic frameworks (MOFs) represent a new class of hybrid organic-inorganic supramolecular materials comprised of ordered networks formed from organic electron donor linkers and metal cations. They can exhibit extremely high surface areas, as well as tunable pore size and functionality, and can act as hosts for a variety of guest molecules. Since their discovery, MOFs have enjoyed extensive exploration, with applications ranging from gas storage to drug delivery to sensing. This review covers advances in the MOF field from the past three years, focusing on applications, including gas separation, catalysis, drug delivery, optical and electronic applications, and sensing. We also summarize recent work on methods for MOF synthesis and computational modeling.
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Affiliation(s)
- Scott T Meek
- Sandia National Laboratories, Livermore, CA 94551-0969, USA
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Krishna R, van Baten JM. Entropy-based separation of linear chain molecules by exploiting differences in the saturation capacities in cage-type zeolites. Sep Purif Technol 2011. [DOI: 10.1016/j.seppur.2010.10.023] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
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Calero S, Martín-Calvo A, Hamad S, García-Pérez E. On the performance of Cu-BTC metal organic framework for carbon tetrachloride gas removal. Chem Commun (Camb) 2011; 47:508-10. [DOI: 10.1039/c0cc02194f] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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Krishna R, van Baten JM. In silico screening of metal–organic frameworks in separation applications. Phys Chem Chem Phys 2011; 13:10593-616. [DOI: 10.1039/c1cp20282k] [Citation(s) in RCA: 277] [Impact Index Per Article: 21.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022]
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Gutiérrez-Sevillano JJ, Caro-Pérez A, Dubbeldam D, Calero S. Molecular simulation investigation into the performance of Cu–BTC metal–organic frameworks for carbon dioxide–methane separations. Phys Chem Chem Phys 2011; 13:20453-60. [DOI: 10.1039/c1cp21761e] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
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Martín-Calvo A, García-Pérez E, García-Sánchez A, Bueno-Pérez R, Hamad S, Calero S. Effect of air humidity on the removal of carbon tetrachloride from air using Cu–BTC metal–organic framework. Phys Chem Chem Phys 2011; 13:11165-74. [DOI: 10.1039/c1cp20168a] [Citation(s) in RCA: 33] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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Highlighting pitfalls in the Maxwell–Stefan modeling of water–alcohol mixture permeation across pervaporation membranes. J Memb Sci 2010. [DOI: 10.1016/j.memsci.2010.05.049] [Citation(s) in RCA: 35] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
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D'Alessandro D, Smit B, Long J. Carbon Dioxide Capture: Prospects for New Materials. Angew Chem Int Ed Engl 2010; 49:6058-82. [DOI: 10.1002/anie.201000431] [Citation(s) in RCA: 3126] [Impact Index Per Article: 223.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
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D'Alessandro D, Smit B, Long J. Abscheidung von Kohlendioxid: Perspektiven für neue Materialien. Angew Chem Int Ed Engl 2010. [DOI: 10.1002/ange.201000431] [Citation(s) in RCA: 282] [Impact Index Per Article: 20.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
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42
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Krishna R, van Baten JM. Hydrogen bonding effects in adsorption of water-alcohol mixtures in zeolites and the consequences for the characteristics of the Maxwell-Stefan diffusivities. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2010; 26:10854-10867. [PMID: 20411951 DOI: 10.1021/la100737c] [Citation(s) in RCA: 78] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/26/2023]
Abstract
This work highlights a variety of peculiar characteristics of adsorption and diffusion of polar molecules such as water, methanol and ethanol in zeolites. These peculiarities are investigated with the aid of configurational-bias Monte Carlo (CBMC) simulations of adsorption isotherms, and molecular dynamics (MD) simulations of diffusivities in FAU, MFI, DDR, and LTA zeolites. Because of strong hydrogen bonding, significant clustering of the guest molecules occurs in all investigated structures. Because of molecular clustering, the inverse thermodynamic factor 1/Gamma(i) identical with (d[ln c(i)])/(d[ln f(i)]) exceeds unity for a range molar concentrations c(i) within the micropores. The degree of clustering is lowered as the temperature is increased. For the concentration ranges for which 1/Gamma(i) > 1, the Fick diffusivity, D(i), for unary diffusion is often lower than both the Maxwell-Stefan, D(i), and the self-diffusivity, D(i,self). For water-alcohol mixtures, the hydrogen bonding between water and alcohol molecules is much more predominant than for water-water, and alcohol-alcohol molecule pairs. Consequently, the adsorption of water-alcohol mixtures shows significant deviations from the predictions of the ideal adsorbed solution theory (IAST). The water-alcohol bonding also leaves its imprint on the mixture diffusion characteristics. The Maxwell-Stefan diffusivity, D(i), of either component in water-alcohol mixtures is lower than the corresponding values of the pure components; this behavior is distinctly different from that for mixtures of nonpolar guest molecules. The binary exchange coefficient D(12) for water-alcohol mixtures is also significantly lower than either self-exchange coefficients D(11) and D(22) of the constituent species. This implies that correlation effects are significantly stronger in water-alcohol mixtures than for the constituent species. Correlation effects are found to be significant for water-alcohol mixture diffusion in DDR and LTA zeolites, even though such effects are negligible for the pure constituents. The major conclusion to emerge from this investigation is that, unlike mixtures of nonpolar molecules, it is not possible to estimate water-alcohol mixture adsorption and diffusion characteristics on the basis of pure component data.
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Affiliation(s)
- Rajamani Krishna
- Van't Hoff Institute for Molecular Sciences, University of Amsterdam, Science Park 904, 1098 XH Amsterdam, The Netherlands.
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Botas JA, Calleja G, Sánchez-Sánchez M, Orcajo MG. Cobalt doping of the MOF-5 framework and its effect on gas-adsorption properties. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2010; 26:5300-5303. [PMID: 20334392 DOI: 10.1021/la100423a] [Citation(s) in RCA: 111] [Impact Index Per Article: 7.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/26/2023]
Abstract
Partial isomorphic substitution of Zn in IRMOF metal clusters by cobalt ions is described for the first time. Specifically, different numbers of Co(2+) ions have been incorporated during solvothermal crystallization into the Zn-based MOF-5 (IRMOF-1) framework, which is one of the most studied MOF materials. The amount of Zn that can be substituted seems to be limited, being no more than 25% of total metal content, that is, no more than one Co atom inside every metal cluster formed by four transition-metal ions, on average. Several characterization techniques, including X-ray diffraction, DR UV-visible spectroscopy, N(2) adsorption isotherms, and thermogravimetrical analysis, strongly support the effective incorporation of Co into the material framework. As-synthesized CoMOF-5 has cobalt ions in octahedral coordination, changing to tetrahedral by simple evacuation, presumably by the removal of two diethylformamide molecules per Co ion. Moreover, the H(2), CH(4), and CO(2) uptake of MOF-5 materials systematically increases with the Co content, particularly at high pressure. Such an increase is moderate anyway, considering that Co is incorporated into unexposed metal sites that are less accessible to gas molecules.
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Affiliation(s)
- Juan A Botas
- Department of Chemical and Energy Technology, ESCET, Universidad Rey Juan Carlos, C/Tulipan s/n, 28933 Mostoles, Madrid, Spain.
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