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Aziz MT, Naqvi SAR, Janjua MRSA, Alam M, Gill WA. Exploring the adsorption behavior of molecular hydrogen on CHA-zeolite by comparing the performance of various force field methods. RSC Adv 2023; 13:30937-30950. [PMID: 37876651 PMCID: PMC10591995 DOI: 10.1039/d3ra04262f] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/25/2023] [Accepted: 10/12/2023] [Indexed: 10/26/2023] Open
Abstract
Molecular hydrogen (H2) adsorption plays a crucial role in numerous applications, including hydrogen storage and purification processes. Understanding the interaction of H2 with porous materials is essential for designing efficient adsorption systems. In this study, we investigate H2 adsorption on CHA-zeolite using a combination of density functional theory (DFT) and force field-based molecular dynamics (MD) simulations. Firstly, we employ DFT calculations to explore the energetic properties and adsorption sites of H2 on the CHA-zeolite framework. The electronic structure and binding energies of H2 in various adsorption configurations are analyzed, providing valuable insights into the nature of the adsorption process. Subsequently, force field methods are employed to perform extensive MD simulations, allowing us to study the dynamic behavior of H2 molecules adsorbed on the CHA-zeolite surface. The trajectory analysis provides information on the diffusion mechanisms and mobility of H2 within the porous structure, shedding light on the transport properties of the adsorbed gas. Furthermore, the combination of DFT and MD results enables us to validate and refine the force field parameters used in simulations, improving the accuracy of the model, and enhancing our understanding of the H2-CHA interactions. Our comprehensive investigation into molecular hydrogen adsorption on CHA-zeolite using density functional theory and molecular dynamics simulations yields valuable insights into the fundamental aspects of the adsorption process. These findings contribute to the development of advanced hydrogen storage and separation technologies, paving the way for efficient and sustainable energy applications.
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Affiliation(s)
- Muhammad Tariq Aziz
- Department of Chemistry, Government College University Faisalabad Faisalabad 38000 Pakistan
| | - Syed Ali Raza Naqvi
- Department of Chemistry, Government College University Faisalabad Faisalabad 38000 Pakistan
| | | | - Manawwer Alam
- Department of Chemistry, College of Science, King Saud University Riyadh 11451 Saudi Arabia
| | - Waqas Amber Gill
- Departamento de Química Física, Universidad de Valencia Avda Dr Moliner, 50, E-46100 Burjassot Valencia Spain
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2
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Gu S, Zhang W, Chen Z, Wang H, You C. Enhancement of citric acid on low-grade limestone wet desulfurization performance coupled with spray and partial bubble technology. Sep Purif Technol 2022. [DOI: 10.1016/j.seppur.2022.120931] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
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3
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Krishna R, van Baten JM. Highlighting the Anti-Synergy between Adsorption and Diffusion in Cation-Exchanged Faujasite Zeolites. ACS OMEGA 2022; 7:13050-13056. [PMID: 35474830 PMCID: PMC9026072 DOI: 10.1021/acsomega.2c00427] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 01/21/2022] [Accepted: 03/14/2022] [Indexed: 06/14/2023]
Abstract
Using configurational-bias Monte Carlo simulations of adsorption equilibrium and molecular dynamics simulations of guest diffusivities of CO2, CH4, N2, and O2 in FAU zeolites with varying amounts of extra-framework cations (Na+ or Li+), we demonstrate that adsorption and diffusion do not, in general, proceed hand-in-hand. Stronger adsorption often implies reduced mobility. The anti-synergy between adsorption and diffusion has consequences for the design and development of pressure-swing adsorption and membrane separation technologies for CO2 capture and N2/O2 separations.
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4
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Tang YB, Xie SJ. Structure and dynamics of a water/methanol mixture confined in zeolitic imidazolate framework ZIF-8 from atomistic simulations. Phys Chem Chem Phys 2022; 24:5220-5232. [PMID: 35167632 DOI: 10.1039/d1cp05571b] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
A classical atomistic simulation study is reported for the microscopic structure and dynamics of a water/methanol mixture confined in flexible nanoporous zeolitic imidazolate framework ZIF-8. Both the radial density distribution and vivid two-dimensional density profile demonstrate that methanol molecules can roughly be viewed as "embedded" between two layers of water molecules to form a "sandwich" structure. The reason for the formation of such a specific structure is explained based on the hydrogen-bonding state and the strength of various hydrogen bonds. The investigation of guest molecular diffusion shows that the self-diffusion coefficient of confined water is generally one to two orders of magnitude smaller than that of bulk water. In addition, the dependence of the self-diffusion coefficient on loading is non-monotonic: the self-diffusion coefficient firstly shows a significant increase and then decreases at higher loading. Moreover, both the structure and dynamics of the hydrogen bond (HB) network of confined water molecules are investigated in a spatially resolved manner. The results indicate that both the HB structure and dynamics of water molecules near the ZIF-8 surface deviate significantly from those of bulk water. However, while water molecules located at the pore center are relatively similar to bulk water molecules with respect to the HB structure, they exhibit strong slowdown in HB dynamics when compared with bulk water. This simulation study elucidates in detail the structural and dynamical properties of a water/methanol mixture in nanoscopic ZIF-8 confinement, which is expected to provide a deep insight into the role of porous fillers, such as ZIF-8, in improving the performance of the dehydration of alcohols via pervaporation and other related processes.
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Affiliation(s)
- Yu-Bo Tang
- Center for Membrane Separation and Water Science & Technology, Zhejiang University of Technology, Hangzhou 310014, P. R. China.
| | - Shi-Jie Xie
- Center for Membrane Separation and Water Science & Technology, Zhejiang University of Technology, Hangzhou 310014, P. R. China.
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Hung TH, Deng X, Lyu Q, Lin LC, Kang DY. Coulombic effect on permeation of CO2 in metal-organic framework membranes. J Memb Sci 2021. [DOI: 10.1016/j.memsci.2021.119742] [Citation(s) in RCA: 13] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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6
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Krishna R, van Baten JM. Using Molecular Simulations to Unravel the Benefits of Characterizing Mixture Permeation in Microporous Membranes in Terms of the Spreading Pressure. ACS OMEGA 2020; 5:32769-32780. [PMID: 33376915 PMCID: PMC7759009 DOI: 10.1021/acsomega.0c05269] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 10/28/2020] [Accepted: 11/30/2020] [Indexed: 06/12/2023]
Abstract
The separation performance of microporous crystalline materials in membrane constructs is dictated by a combination of mixture adsorption and intracrystalline diffusion characteristics; the permeation selectivity S perm is a product of the adsorption selectivity S ads and the diffusion selectivity, S diff. The primary objective of this article is to gain fundamental insights into S ads and S diff by use of molecular simulations. We performed configurational-bias Monte Carlo (CBMC) simulations of mixture adsorption equilibrium and molecular dynamics (MD) simulations of guest self-diffusivities of a number of binary mixtures of light gaseous molecules (CO2, CH4, N2, H2, and C2H6) in a variety of microporous hosts of different pore dimensions and topologies. Irrespective of the bulk gas compositions and bulk gas fugacities, the adsorption selectivity, S ads, is found to be uniquely determined by the adsorption potential, Φ, a convenient and practical proxy for the spreading pressure π that is calculable using the ideal adsorbed solution theory for mixture adsorption equilibrium. The adsorption potential Φ is also a proxy for the pore occupancy and is the thermodynamically appropriate yardstick to determine the loading and composition dependences of intracrystalline diffusivities and diffusion selectivities, S diff. When compared at the same Φ, the component permeabilities, Π i for CO2, CH4, and N2, determinable from CBMC/MD data, are found to be independent of the partners in the various mixtures investigated and have practically the same values as the values for the corresponding unary permeabilities. In all investigated systems, the H2 permeability in a mixture is significantly lower than the corresponding unary value. These reported results have important practical consequences in process development and are also useful for screening of materials for use as membrane devices.
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7
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Abstract
AbstractMeasurement of molecular diffusion in nanoporous host materials, which are typically inhomogeneous and anisotropic, often involves an intricate web of factors and relations to be taken into account since the associated diffusivities are a function of the diffusion path of the guest molecules during a given observation time. Depending on the observation time, therefore, the result of the experimental measurement can point to completely different conclusions about the underlying diffusion phenomena. The risk of misinterpretation of the experimental data, by correlating them with irrelevant phenomena, may be reduced if there is an option to compare the data with the results of totally independent measurements. The present communication addresses this issue with reference to the particular potentials of pulsed field gradient NMR and microimaging by infrared microscopy as techniques of microscopic diffusion measurement.
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8
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Xiao Y, Zhou M, He G. Equilibrium and Diffusion of CO2 Adsorption on Micro-Mesoporous NaX/MCM-41 via Molecular Simulation. Ind Eng Chem Res 2019. [DOI: 10.1021/acs.iecr.9b02670] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- Yonghou Xiao
- Panjin Institute of Industrial Technology, Dalian University of Technology, Panjin 124221, China
- State Key Laboratory of Fine Chemicals, School of Petroleum and Chemical Engineering, Dalian University of Technology, Panjin 124221, China
| | - Mengxue Zhou
- State Key Laboratory of Fine Chemicals, School of Petroleum and Chemical Engineering, Dalian University of Technology, Panjin 124221, China
| | - Gaohong He
- Panjin Institute of Industrial Technology, Dalian University of Technology, Panjin 124221, China
- State Key Laboratory of Fine Chemicals, School of Petroleum and Chemical Engineering, Dalian University of Technology, Panjin 124221, China
- Supercomputing Center, Dalian University of Technology, Dalian 116024, China
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Krishna R. Highlighting the Influence of Thermodynamic Coupling on Kinetic Separations with Microporous Crystalline Materials. ACS OMEGA 2019; 4:3409-3419. [PMID: 30847432 PMCID: PMC6398361 DOI: 10.1021/acsomega.8b03480] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/12/2018] [Accepted: 01/31/2019] [Indexed: 06/02/2023]
Abstract
The main focus of this article is on mixture separations that are driven by differences in intracrystalline diffusivities of guest molecules in microporous crystalline adsorbent materials. Such "kinetic" separations serve to over-ride, and reverse, the selectivities dictated by mixture adsorption equilibrium. The Maxwell-Stefan formulation for the description of intracrystalline fluxes shows that the flux of each species is coupled with that of the partner species. For n-component mixtures, the coupling is quantified by a n × n dimensional matrix of thermodynamic correction factors with elements Γ ij ; these elements can be determined from the model used to describe the mixture adsorption equilibrium. If the thermodynamic coupling effects are essentially ignored, i.e., the Γ ij is assumed to be equal to δ ij , the Kronecker delta, the Maxwell-Stefan formulation degenerates to yield uncoupled flux relations. The significance of thermodynamic coupling is highlighted by detailed analysis of separations of five different mixtures: N2/CH4, CO2/C2H6, O2/N2, C3H6/C3H8, and hexane isomers. In all cases, the productivity of the purified raffinate, containing the tardier species, is found to be significantly larger than that anticipated if the simplification Γ ij = δ ij is assumed. The reason for the strong influence of Γ ij on transient breakthroughs is traceable to the phenomenon of uphill intracrystalline diffusion of more mobile species. The major conclusion to emerge from this study is that modeling of kinetic separations needs to properly account for the thermodynamic coupling effects.
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Boon N. Efficient configurational-bias Monte-Carlo simulations of chain molecules with "swarms" of trial configurations. J Chem Phys 2018; 149:064109. [PMID: 30111122 DOI: 10.1063/1.5029566] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/24/2023] Open
Abstract
The pruned-enriched Rosenbluth method (PERM) is a popular and powerful Monte-Carlo technique for sampling flexible chain polymers of substantial length. In its original form, however, the method cannot be applied in Markov-chain Monte-Carlo schemes, which has rendered PERM unsuited for systems that consist of many chains. The current work builds on the configurational-bias Monte-Carlo (CBMC) method. The growth of a large set of trial configurations in each move is governed by simultaneous pruning and enrichment events, which tend to replace configurations with a low statistical weight by clones of stronger configurations. In simulations of dense brushes of flexible chains, a gain in efficiency of at least three orders of magnitude is observed with respect to CBMC and one order of magnitude with respect to recoil-growth approaches. Moreover, meaningful statistics can be collected from all trial configurations through the so-called "waste-recycling" Monte Carlo scheme.
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Affiliation(s)
- Niels Boon
- Division of Physical Chemistry, Department of Chemistry, Lund University, SE-22100 Lund, Sweden
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11
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Abstract
Chemical reactor modelling based on insights and data on a molecular level has become reality over the last few years. Multiscale models describing elementary reaction steps and full microkinetic schemes, pore structures, multicomponent adsorption and diffusion inside pores, and entire reactors have been presented. Quantum mechanical (QM) approaches, molecular simulations (Monte Carlo and molecular dynamics), and continuum equations have been employed for this purpose. Some recent developments in these approaches are presented, in particular time-dependent QM methods, calculation of van der Waals forces, new approaches for force field generation, automatic setup of reaction schemes, and pore modelling. Multiscale simulations are discussed. Applications of these approaches to heterogeneous catalysis are demonstrated for examples that have found growing interest over the last few years, such as metal-support interactions, influence of pore geometry on reactions, noncovalent bonding, reaction dynamics, dynamic changes in catalyst nanoparticle structure, electrocatalysis, solvent effects in catalysis, and multiscale modelling.
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Affiliation(s)
- Frerich J. Keil
- Department of Chemical Engineering, Hamburg University of Technology, D-21073 Hamburg, Germany
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12
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The Maxwell–Stefan description of mixture permeation across nanoporous graphene membranes. Chem Eng Res Des 2018. [DOI: 10.1016/j.cherd.2018.03.033] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
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13
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Krishna R. Methodologies for screening and selection of crystalline microporous materials in mixture separations. Sep Purif Technol 2018. [DOI: 10.1016/j.seppur.2017.11.056] [Citation(s) in RCA: 43] [Impact Index Per Article: 7.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
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14
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Gotzias A. The effect of gme topology on multicomponent adsorption in zeolitic imidazolate frameworks. Phys Chem Chem Phys 2018; 19:871-877. [PMID: 27942634 DOI: 10.1039/c6cp06036f] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
We employ a simulation approach to study the adsorption of single, binary and ternary mixtures on eight gme Zeolitic Imidazolate Frameworks (ZIFs) at 298 K. Four adsorbate fluids were considered; carbon dioxide, methane, nitrogen and water. We compute the high pressure adsorption density profiles inside the micropore channels of each crystal. The profiles are compared directly for the different structures and adsorbate components and used to highlight the influence of the imidazolate ligands on pure and competitive adsorption. ZIFs with long ligands reveal an additional, accessible to the fluid space detected for the first time. This is a wedged volume on one direction of the pore walls, shaped thus because the long ligands tilt in order to be connected. We estimate the pressure required for water to become the dominating competing adsorbate within different crystal cavities. The simulated data for CO2 adsorption in ZIF69 strongly correlate with a set of Raman spectroscopy intensity values that correspond to the same adsorbate-adsorbent system.
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Affiliation(s)
- Anastasios Gotzias
- Institute of Nanoscience and Nanotechnology, NCSR Demokritos, Athens, Greece.
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15
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Krishna R. A Maxwell-Stefan-Glueckauf description of transient mixture uptake in microporous adsorbents. Sep Purif Technol 2018. [DOI: 10.1016/j.seppur.2017.09.057] [Citation(s) in RCA: 9] [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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16
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Krishna R. Using the Maxwell-Stefan formulation for highlighting the influence of interspecies (1−2) friction on binary mixture permeation across microporous and polymeric membranes. J Memb Sci 2017. [DOI: 10.1016/j.memsci.2017.06.062] [Citation(s) in RCA: 29] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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17
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Krekelberg WP, Siderius DW, Shen VK, Truskett TM, Errington JR. Connection Between Thermodynamics and Dynamics of Simple Fluids in Pores: Impact of Fluid-Fluid Interaction Range and Fluid-Solid Interaction Strength. THE JOURNAL OF PHYSICAL CHEMISTRY. C, NANOMATERIALS AND INTERFACES 2017; 121:16316-16327. [PMID: 29170685 PMCID: PMC5695693 DOI: 10.1021/acs.jpcc.7b04232] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/30/2023]
Abstract
Using molecular simulations, we investigate how the range of fluid-fluid (adsorbate-adsorbate) interactions and the strength of fluid-solid (adsorbate-adsorbent) interactions impact the strong connection between distinct adsorptive regimes and distinct self-diffusivity regimes reported in [Krekelberg, W. P.; Siderius, D. W.; Shen, V. K.; Truskett, T. M.; Errington, J. R. Langmuir2013, 29, 14527-14535]. Although increasing the fluid-fluid interaction range changes both the thermodynamics and the dynamic properties of adsorbed fluids, the previously reported connection between adsorptive filling regimes and self-diffusivity regimes remains. Increasing the fluid-fluid interaction range leads to enhanced layering and decreased self-diffusivity in the multilayer-formation regime but has little effect on the properties within film-formation and pore-filling regimes. We also find that weakly attractive adsorbents, which do not display distinct multilayer formation, are hard-sphere-like at super- and subcritical temperatures. In this case, the self-diffusivity of the confined and bulk fluid has a nearly identical scaling-relationship with effective density.
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Affiliation(s)
- William P. Krekelberg
- Chemical Sciences Division, National Institute of Standards and Technology, Gaithersburg, Maryland 20899-8320, USA
| | - Daniel W. Siderius
- Chemical Sciences Division, National Institute of Standards and Technology, Gaithersburg, Maryland 20899-8320, USA
| | - Vincent K. Shen
- Chemical Sciences Division, National Institute of Standards and Technology, Gaithersburg, Maryland 20899-8320, USA
| | - Thomas M. Truskett
- McKetta Department of Chemical Engineering, The University of Texas at Austin, Austin, Texas 78712, USA
| | - Jeffrey R. Errington
- Department of Chemical and Biological Engineering, University at Buffalo, The State University of New York, Buffalo, New York 14260, USA
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18
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Goetze J, Meirer F, Yarulina I, Gascon J, Kapteijn F, Ruiz-Martínez J, Weckhuysen BM. Insights into the Activity and Deactivation of the Methanol-to-Olefins Process over Different Small-Pore Zeolites As Studied with Operando UV-vis Spectroscopy. ACS Catal 2017; 7:4033-4046. [PMID: 28603658 PMCID: PMC5460665 DOI: 10.1021/acscatal.6b03677] [Citation(s) in RCA: 94] [Impact Index Per Article: 13.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/26/2016] [Revised: 04/23/2017] [Indexed: 11/28/2022]
Abstract
The nature and evolution of the hydrocarbon pool (HP) species during the Methanol-to-Olefins (MTO) process for three small-pore zeolite catalysts, with a different framework consisting of large cages interconnected by small eight-ring windows (CHA, DDR, and LEV) was studied at reaction temperatures between 350 and 450 °C using a combination of operando UV-vis spectroscopy and online gas chromatography. It was found that small differences in cage size, shape, and pore structure of the zeolite frameworks result in the generation of different hydrocarbon pool species. More specifically, it was found that the large cage of CHA results in the formation of a wide variety of hydrocarbon pool species, mostly alkylated benzenes and naphthalenes. In the DDR cage, 1-methylnaphthalene is preferentially formed, while the small LEV cage generally contains fewer hydrocarbon pool species. The nature and evolution of these hydrocarbon pool species was linked with the stage of the reaction using a multivariate analysis of the operando UV-vis spectra. In the 3-D pore network of CHA, the reaction temperature has only a minor effect on the performance of the MTO catalyst. However, for the 2-D pore networks of DDR and LEV, an increase in the applied reaction temperature resulted in a dramatic increase in catalytic activity. For all zeolites in this study, the role of the hydrocarbon species changes with reaction temperature. This effect is most clear in DDR, in which diamantane and 1-methylnaphthalene are deactivating species at a reaction temperature of 350 °C, whereas at higher temperatures diamantane formation is not observed and 1-methylnaphthalene is an active species. This results in a different amount and nature of coke species in the deactivated catalyst, depending on zeolite framework and reaction temperature.
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Affiliation(s)
- Joris Goetze
- Inorganic
Chemistry and Catalysis, Debye Institute for Nanomaterials Science, Utrecht University, Universiteitsweg 99, 3584 CG Utrecht, The Netherlands
| | - Florian Meirer
- Inorganic
Chemistry and Catalysis, Debye Institute for Nanomaterials Science, Utrecht University, Universiteitsweg 99, 3584 CG Utrecht, The Netherlands
| | - Irina Yarulina
- Catalysis
Engineering, Chemical Engineering Department, Delft University of Technology, Van der Maasweg 9, 2629 HZ Delft, The Netherlands
| | - Jorge Gascon
- Catalysis
Engineering, Chemical Engineering Department, Delft University of Technology, Van der Maasweg 9, 2629 HZ Delft, The Netherlands
| | - Freek Kapteijn
- Catalysis
Engineering, Chemical Engineering Department, Delft University of Technology, Van der Maasweg 9, 2629 HZ Delft, The Netherlands
| | - Javier Ruiz-Martínez
- Inorganic
Chemistry and Catalysis, Debye Institute for Nanomaterials Science, Utrecht University, Universiteitsweg 99, 3584 CG Utrecht, The Netherlands
| | - Bert M. Weckhuysen
- Inorganic
Chemistry and Catalysis, Debye Institute for Nanomaterials Science, Utrecht University, Universiteitsweg 99, 3584 CG Utrecht, The Netherlands
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19
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Ni F, Wang G, Zhao H. Molecular and condition parameters dependent diffusion coefficient of water in poly(vinyl alcohol): a molecular dynamics simulation study. Colloid Polym Sci 2017. [DOI: 10.1007/s00396-017-4077-x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/19/2022]
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20
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Krishna R, Baur R, van Baten JM. Highlighting diffusional coupling effects in zeolite catalyzed reactions by combining the Maxwell–Stefan and Langmuir–Hinshelwood formulations. REACT CHEM ENG 2017. [DOI: 10.1039/c7re00001d] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/27/2023]
Abstract
The combined phenomena of intra-crystalline adsorption, diffusion and reversible chemical reactions inside microporous crystalline zeolite catalyst particles are described by combining the Langmuir–Hinshelwood kinetics with the Maxwell–Stefan (M–S) diffusion formulation.
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Affiliation(s)
- Rajamani Krishna
- Van 't Hoff Institute for Molecular Sciences
- University of Amsterdam
- 1098 XH Amsterdam
- The Netherlands
| | - Richard Baur
- Van 't Hoff Institute for Molecular Sciences
- University of Amsterdam
- 1098 XH Amsterdam
- The Netherlands
| | - Jasper M. van Baten
- Van 't Hoff Institute for Molecular Sciences
- University of Amsterdam
- 1098 XH Amsterdam
- The Netherlands
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21
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Fasano M, Humplik T, Bevilacqua A, Tsapatsis M, Chiavazzo E, Wang EN, Asinari P. Interplay between hydrophilicity and surface barriers on water transport in zeolite membranes. Nat Commun 2016; 7:12762. [PMID: 27694935 PMCID: PMC5477497 DOI: 10.1038/ncomms12762] [Citation(s) in RCA: 67] [Impact Index Per Article: 8.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/08/2016] [Accepted: 08/01/2016] [Indexed: 01/16/2023] Open
Abstract
A comprehensive understanding of molecular transport within nanoporous materials remains elusive in a broad variety of engineering and biomedical applications. Here, experiments and atomistic simulations are synergically used to elucidate the non-trivial interplay between nanopore hydrophilicity and surface barriers on the overall water transport through zeolite crystals. At these nanometre-length scales, these results highlight the dominating effect of surface imperfections with reduced permeability on the overall water transport. A simple diffusion resistance model is shown to be sufficient to capture the effects of both intracrystalline and surface diffusion resistances, thus properly linking simulation to experimental evidence. This work suggests that future experimental work should focus on eliminating/overcoming these surface imperfections, which promise an order of magnitude improvement in permeability. Zeolite crystal with porous structure is predicted to be a good membrane material for water purification, but experiments show water uptake orders of magnitude smaller than the theory. Here, Fasano et al. attribute this disagreement to the additional diffusion resistance induced by surface defects.
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Affiliation(s)
- Matteo Fasano
- Department of Energy, Politecnico di Torino, Corso Duca degli Abruzzi 24, Torino 10129, Italy
| | - Thomas Humplik
- Department of Mechanical Engineering, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139, USA
| | - Alessio Bevilacqua
- Department of Energy, Politecnico di Torino, Corso Duca degli Abruzzi 24, Torino 10129, Italy
| | - Michael Tsapatsis
- Department of Chemical Engineering and Materials Science, University of Minnesota, Minneapolis, Minnesota 55455, USA
| | - Eliodoro Chiavazzo
- Department of Energy, Politecnico di Torino, Corso Duca degli Abruzzi 24, Torino 10129, Italy
| | - Evelyn N Wang
- Department of Mechanical Engineering, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139, USA
| | - Pietro Asinari
- Department of Energy, Politecnico di Torino, Corso Duca degli Abruzzi 24, Torino 10129, Italy
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22
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Golchoobi A, Pahlavanzadeh H. Molecular simulation, experiments and modelling of single adsorption capacity of 4A molecular sieve for CO2–CH4 separation. SEP SCI TECHNOL 2016. [DOI: 10.1080/01496395.2016.1206571] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
Affiliation(s)
- Abdollah Golchoobi
- Faculty of Chemical Engineering, Tarbiat Modarres University, Tehran, Iran
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24
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Titze T, Lauerer A, Heinke L, Chmelik C, Zimmermann NER, Keil FJ, Ruthven DM, Kärger J. Transport in Nanoporous Materials Including MOFs: The Applicability of Fick’s Laws. Angew Chem Int Ed Engl 2015; 54:14580-3. [DOI: 10.1002/anie.201506954] [Citation(s) in RCA: 67] [Impact Index Per Article: 7.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/27/2015] [Indexed: 11/09/2022]
Affiliation(s)
- Tobias Titze
- Department of Interface Physics, University of Leipzig, Linnéstrasse 5, 04103 Leipzig (Germany)
| | - Alexander Lauerer
- Department of Interface Physics, University of Leipzig, Linnéstrasse 5, 04103 Leipzig (Germany)
| | - Lars Heinke
- Institute of Functional Interfaces, Karlsruher Institut für Technologie, Karlsruhe (Germany)
| | - Christian Chmelik
- Department of Interface Physics, University of Leipzig, Linnéstrasse 5, 04103 Leipzig (Germany)
| | - Nils E. R. Zimmermann
- Computational Research Division, Lawrence Berkeley National Laboratory, Berkeley, (USA)
| | - Frerich J. Keil
- Department of Chemical Reaction Engineering, Hamburg University of Technology, Hamburg (Germany)
| | | | - Jörg Kärger
- Department of Interface Physics, University of Leipzig, Linnéstrasse 5, 04103 Leipzig (Germany)
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25
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Titze T, Lauerer A, Heinke L, Chmelik C, Zimmermann NER, Keil FJ, Ruthven DM, Kärger J. Transport in nanoporösen Materialien, einschließlich MOFs: über die Anwendbarkeit der Fickschen Gesetze. Angew Chem Int Ed Engl 2015. [DOI: 10.1002/ange.201506954] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/12/2023]
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26
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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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27
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Odoh SO, Cramer CJ, Truhlar DG, Gagliardi L. Quantum-Chemical Characterization of the Properties and Reactivities of Metal–Organic Frameworks. Chem Rev 2015; 115:6051-111. [DOI: 10.1021/cr500551h] [Citation(s) in RCA: 206] [Impact Index Per Article: 22.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
Affiliation(s)
- Samuel O. Odoh
- Department of Chemistry,
Chemical Theory Center, and Supercomputing Institute, University of Minnesota, Minneapolis, Minnesota 55455-0431, United States
| | - Christopher J. Cramer
- Department of Chemistry,
Chemical Theory Center, and Supercomputing Institute, University of Minnesota, Minneapolis, Minnesota 55455-0431, United States
| | - Donald G. Truhlar
- Department of Chemistry,
Chemical Theory Center, and Supercomputing Institute, University of Minnesota, Minneapolis, Minnesota 55455-0431, United States
| | - Laura Gagliardi
- Department of Chemistry,
Chemical Theory Center, and Supercomputing Institute, University of Minnesota, Minneapolis, Minnesota 55455-0431, United States
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28
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Chen DL, Shang H, Zhu W, Krishna R. Reprint of: Transient breakthroughs of CO 2 /CH 4 and C 3 H 6 /C 3 H 8 mixtures in fixed beds packed with Ni-MOF-74. Chem Eng Sci 2015. [DOI: 10.1016/j.ces.2014.12.001] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/24/2022]
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29
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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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30
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Rangnekar N, Mittal N, Elyassi B, Caro J, Tsapatsis M. Zeolite membranes – a review and comparison with MOFs. Chem Soc Rev 2015; 44:7128-54. [DOI: 10.1039/c5cs00292c] [Citation(s) in RCA: 490] [Impact Index Per Article: 54.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
Abstract
The latest developments in zeolite and MOF membranes are reviewed, with an emphasis on synthesis techniques. Industrial applications, hydrothermal stability, polymer-supported and mixed matrix membranes are some of the aspects discussed.
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Affiliation(s)
- N. Rangnekar
- Department of Chemical Engineering and Materials Science
- Minneapolis
- USA
| | - N. Mittal
- Department of Chemical Engineering and Materials Science
- Minneapolis
- USA
| | - B. Elyassi
- Department of Chemical Engineering and Materials Science
- Minneapolis
- USA
| | - J. Caro
- Institut für Physikalische Chemie und Elektrochemie der Leibniz Universität Hannover
- D-30167 Hannover
- Germany
| | - M. Tsapatsis
- Department of Chemical Engineering and Materials Science
- Minneapolis
- USA
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31
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Abstract
Diffusional coupling effects may cause uphill transport of a species against its concentration gradient. Transient overshoots and serpentine equilibration trajectories in composition space are fingerprints of uphill diffusion. Serpentine diffusion trajectories may enter meta-stable zones, leading to spontaneous emulsification and the Ouzo effect.
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Affiliation(s)
- Rajamani Krishna
- Van't Hoff Institute for Molecular Sciences
- University of Amsterdam
- 1098 XH Amsterdam
- The Netherlands
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32
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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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33
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Fasano M, Chiavazzo E, Asinari P. Water transport control in carbon nanotube arrays. NANOSCALE RESEARCH LETTERS 2014; 9:559. [PMID: 25313305 PMCID: PMC4194061 DOI: 10.1186/1556-276x-9-559] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/13/2014] [Accepted: 09/25/2014] [Indexed: 05/31/2023]
Abstract
Based on a recent scaling law of the water mobility under nanoconfined conditions, we envision novel strategies for precise modulation of water diffusion within membranes made of carbon nanotube arrays (CNAs). In a first approach, the water diffusion coefficient D may be tuned by finely controlling the size distribution of the pore size. In the second approach, D can be varied at will by means of externally induced electrostatic fields. Starting from the latter strategy, switchable molecular sieves are proposed, where membranes are properly designed with sieving and permeation features that can be dynamically activated/deactivated. Areas where a precise control of water transport properties is beneficial range from energy and environmental engineering up to nanomedicine.
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Affiliation(s)
- Matteo Fasano
- Dipartimento Energia, Politecnico di Torino, Corso Duca degli Abruzzi, 24, 10129 Torino, Italy
| | - Eliodoro Chiavazzo
- Dipartimento Energia, Politecnico di Torino, Corso Duca degli Abruzzi, 24, 10129 Torino, Italy
| | - Pietro Asinari
- Dipartimento Energia, Politecnico di Torino, Corso Duca degli Abruzzi, 24, 10129 Torino, Italy
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34
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Chen DL, Shang H, Zhu W, Krishna R. Transient breakthroughs of CO2/CH4 and C3H6/C3H8 mixtures in fixed beds packed with Ni-MOF-74. Chem Eng Sci 2014. [DOI: 10.1016/j.ces.2014.07.008] [Citation(s) in RCA: 41] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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35
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36
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Krishna R. A Smörgåsbord of Separation Strategies Using Microporous Crystalline Materials. INDIAN CHEMICAL ENGINEER 2014. [DOI: 10.1080/00194506.2014.881000] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
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37
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Kärger J, Binder T, Chmelik C, Hibbe F, Krautscheid H, Krishna R, Weitkamp J. Microimaging of transient guest profiles to monitor mass transfer in nanoporous materials. NATURE MATERIALS 2014; 13:333-343. [PMID: 24651427 DOI: 10.1038/nmat3917] [Citation(s) in RCA: 122] [Impact Index Per Article: 12.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/01/2013] [Accepted: 02/18/2014] [Indexed: 06/03/2023]
Abstract
The intense interactions of guest molecules with the pore walls of nanoporous materials is the subject of continued fundamental research. Stimulated by their thermal energy, the guest molecules in these materials are subject to a continuous, irregular motion, referred to as diffusion. Diffusion, which is omnipresent in nature, influences the efficacy of nanoporous materials in reaction and separation processes. The recently introduced techniques of microimaging by interference and infrared microscopy provide us with a wealth of information on diffusion, hitherto inaccessible from commonly used techniques. Examples include the determination of surface barriers and the sticking coefficient's analogue, namely the probability that, on colliding with the particle surface, a molecule may continue its diffusion path into the interior. Microimaging is further seen to open new vistas in multicomponent guest diffusion (including the detection of a reversal in the preferred diffusion pathways), in guest-induced phase transitions in nanoporous materials and in matching the results of diffusion studies under equilibrium and non-equilibrium conditions.
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Affiliation(s)
- Jörg Kärger
- Department of Interface Physics, University of Leipzig, Linnestrasse 5, 04103 Leipzig, Germany
| | - Tomas Binder
- Department of Interface Physics, University of Leipzig, Linnestrasse 5, 04103 Leipzig, Germany
| | - Christian Chmelik
- Department of Interface Physics, University of Leipzig, Linnestrasse 5, 04103 Leipzig, Germany
| | - Florian Hibbe
- Department of Interface Physics, University of Leipzig, Linnestrasse 5, 04103 Leipzig, Germany
| | - Harald Krautscheid
- Institute of Inorganic Chemistry, University of Leipzig, Johannisallee 29, 04103 Leipzig, Germany
| | - Rajamani Krishna
- Van't Hoff Institute for Molecular Sciences, University of Amsterdam, Science Park 904, 1098 XH Amsterdam, The Netherlands
| | - Jens Weitkamp
- Institute of Chemical Technology, University of Stuttgart, Pfaffenwaldring 55, 70569 Stuttgart, Germany
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38
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Mehlhorn D, Inayat A, Schwieger W, Valiullin R, Kärger J. Probing Mass Transfer in Mesoporous Faujasite-Type Zeolite Nanosheet Assemblies. Chemphyschem 2014; 15:1681-6. [DOI: 10.1002/cphc.201301133] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/28/2013] [Indexed: 11/10/2022]
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39
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Chang G, Bao Z, Ren Q, Deng S, Zhang Z, Su B, Xing H, Yang Y. Fabrication of cuprous nanoparticles in MIL-101: an efficient adsorbent for the separation of olefin–paraffin mixtures. RSC Adv 2014. [DOI: 10.1039/c4ra02125h] [Citation(s) in RCA: 71] [Impact Index Per Article: 7.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
Cu+-doped MIL-101 was synthesized, and its application in the separation of olefin–paraffin was investigated for the first time.
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Affiliation(s)
- Ganggang Chang
- Key Laboratory of Biomass Chemical Engineering of Ministry of Education
- Department of Chemical and Biological Engineering
- Zhejiang University
- Hangzhou 310027, China
| | - Zongbi Bao
- Key Laboratory of Biomass Chemical Engineering of Ministry of Education
- Department of Chemical and Biological Engineering
- Zhejiang University
- Hangzhou 310027, China
| | - Qilong Ren
- Key Laboratory of Biomass Chemical Engineering of Ministry of Education
- Department of Chemical and Biological Engineering
- Zhejiang University
- Hangzhou 310027, China
| | - Shuguang Deng
- Key Laboratory of Biomass Chemical Engineering of Ministry of Education
- Department of Chemical and Biological Engineering
- Zhejiang University
- Hangzhou 310027, China
- Chemical Engineering Department
| | - Zhiguo Zhang
- Key Laboratory of Biomass Chemical Engineering of Ministry of Education
- Department of Chemical and Biological Engineering
- Zhejiang University
- Hangzhou 310027, China
| | - Baogen Su
- Key Laboratory of Biomass Chemical Engineering of Ministry of Education
- Department of Chemical and Biological Engineering
- Zhejiang University
- Hangzhou 310027, China
| | - Huabin Xing
- Key Laboratory of Biomass Chemical Engineering of Ministry of Education
- Department of Chemical and Biological Engineering
- Zhejiang University
- Hangzhou 310027, China
| | - Yiwen Yang
- Key Laboratory of Biomass Chemical Engineering of Ministry of Education
- Department of Chemical and Biological Engineering
- Zhejiang University
- Hangzhou 310027, China
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40
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Krekelberg WP, Siderius DW, Shen VK, Truskett TM, Errington JR. Connection between thermodynamics and dynamics of simple fluids in highly attractive pores. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2013; 29:14527-14535. [PMID: 24160818 DOI: 10.1021/la4037327] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/02/2023]
Abstract
Using molecular simulations, we investigate the structural and diffusive dynamics properties of a model fluid in highly absorptive cylindrical pores. At subcritical temperatures, self-diffusivity displays three distinct regimes as a function of average pore density ρ: (1) a decrease in self-diffusivity with increasing ρ at low ρ, (2) constant self-diffusivity with respect to varying ρ at moderate density, and (3) a decrease in self-diffusivity with increasing ρ at high density. These regimes are closely linked to the thermodynamic properties of the fluid in the pore, specifically, the adsorption isotherm, isosteric heat of adsorption, and the density profile. We show that these three diffusivity regimes qualitatively correspond to three distinct adsorption regimes: monolayer formation, multilayer adsorption, and pore filling, respectively. In addition, we find that the self-diffusivity is a universal function of the local film density in the monolayer formation regime at subcritical temperatures. The results of this work suggest a potential means to estimate the self-diffusivity over a broad pressure range using a limited number of experiments.
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Affiliation(s)
- William P Krekelberg
- Chemical Sciences Division, National Institute of Standards and Technology , Gaithersburg, Maryland 20899-8320, United States
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