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Ta AT, Daouli A, Ullberg RS, Fonseca E, Proust V, Grandjean A, Hennig RG, Zur Loye HC, Badawi M, Phillpot SR. Incorporating solvent effects in DFT: insights from cation exchange in faujasites. Phys Chem Chem Phys 2024; 26:14561-14572. [PMID: 38722083 DOI: 10.1039/d4cp00467a] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/23/2024]
Abstract
Zeolites are versatile materials renowned for their extra-framework cation exchange capabilities, with applications spanning diverse fields, including nuclear waste treatment. While detailed experimental characterization offers valuable insight, density functional theory (DFT) proves particularly adept at investigating ion exchange in zeolites, owing to its atomic and electronic resolution. However, the prevalent occurrence of zeolitic ion exchange in aqueous environments poses a challenge to conventional DFT modeling, traditionally conducted in a vacuum. This study seeks to enhance zeolite modeling by systematically evaluating predictive differences across varying degrees of aqueous solvent inclusion. Specifically focusing on monovalent cation exchange in Na-X zeolites, we explore diverse modeling approaches. These range from simple dehydrated systems (representing bare reference states in vacuum) to more sophisticated models that incorporate aqueous solvent effects through explicit water molecules and/or a dielectric medium. Through comparative analysis of DFT and semi-empirical DFT approaches, along with their validation against experimental results, our findings underscore the necessity to concurrently consider explicit and implicit solvent effects for accurate prediction of zeolitic ionic exchange.
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Affiliation(s)
- An T Ta
- Department of Materials Science and Engineering, University of Florida, Gainesville, FL 32611, USA.
| | - Ayoub Daouli
- Laboratoire Lorrain de Chimie Moléculaire L2CM, Université de Lorraine, CNRS, F-54000 Nancy, France.
| | - R Seaton Ullberg
- Department of Materials Science and Engineering, University of Florida, Gainesville, FL 32611, USA.
| | - Eric Fonseca
- Department of Materials Science and Engineering, University of Florida, Gainesville, FL 32611, USA.
| | - Vanessa Proust
- CEA, DES, ISEC, DMRC, Univ Montpellier, Marcoule, France
| | | | - Richard G Hennig
- Department of Materials Science and Engineering, University of Florida, Gainesville, FL 32611, USA.
| | - Hans-Conrad Zur Loye
- Center for Hierarchical Waste Form Materials and Department of Chemistry and Biochemistry, University of South Carolina, Columbia, South Carolina 29208, USA
| | - Michael Badawi
- Laboratoire Lorrain de Chimie Moléculaire L2CM, Université de Lorraine, CNRS, F-54000 Nancy, France.
| | - Simon R Phillpot
- Department of Materials Science and Engineering, University of Florida, Gainesville, FL 32611, USA.
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Zhao R, Khare R, Zhang Y, Sanchez-Sanchez M, Bermejo-Deval R, Liu Y, Lercher JA. Promotion of adsorptive and catalytic properties of zeolitic Brønsted acid sites by proximal extra-framework Si(OH)x groups. Nat Catal 2023. [DOI: 10.1038/s41929-022-00906-z] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
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Molecular Insights into Adsorption and Diffusion Mechanism of N-Hexane in MFI Zeolites with Different Si-to-Al Ratios and Counterions. Catalysts 2022. [DOI: 10.3390/catal12020144] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023] Open
Abstract
The effect of the silicon to aluminum ratio (SAR) and alkali metal cations on adsorption and diffusion properties of ZSM-5 and silicate-1 zeolites was investigated using n-hexane as the model probe via giant canonical Monte Carlo (GCMC) and molecular dynamics (MD) simulations. A wide range of SAR was considered in this study to explore the possible adsorption sites in the zeolites. The findings show that, at 298 K and 423 K, adsorption and diffusion of n-hexane on/in low SAR (≤50) H-ZSM-5 models were promoted due to the preferable distribution of n-hexane in straight channels and enhanced interaction between protons and n-hexane molecules (about 24 kcal·mol−1). In alkali metal cation (i.e., Na+ and K+) exchanged ZSM-5, the alkali metal cations affected transport of molecules, which led to significant differences in their adsorption and diffusion properties compared to HZSM-5. In the Na+ and K+ systems, lower saturated adsorption capacities were predicted compared to that of silicate-1, which could be attributed to the decrease in effective void size posed by alkali–metal cations. In addition, simulation results also suggested that the T9 and T3 are the most likely sites for n-hexane adsorption, followed by T2, T5, and T10. Findings of the work can be beneficial to the rational design of high-performance zeolite catalysts for n-hexane conversion.
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Tian H, Liu S, Liu Q. HZSM-5 zeolite modification and catalytic reaction mechanism in the reaction of cyclohexene hydration. RSC Adv 2022; 12:24654-24669. [PMID: 36128380 PMCID: PMC9429031 DOI: 10.1039/d2ra04285a] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/12/2022] [Accepted: 08/24/2022] [Indexed: 11/21/2022] Open
Abstract
This study investigated a three-phase (liquid–liquid–solid) reaction system of cyclohexene hydration where the catalyst was hydrophilic at the bottom of the water phase.
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Affiliation(s)
- Hui Tian
- College of Chemistry and Chemical Engineering, Yantai University, Yantai 264005, China
| | - Shuai Liu
- College of Chemistry and Chemical Engineering, Yantai University, Yantai 264005, China
| | - Qing Liu
- College of Chemistry and Chemical Engineering, Yantai University, Yantai 264005, China
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Busca G, Gervasini A. Solid acids, surface acidity and heterogeneous acid catalysis. ADVANCES IN CATALYSIS 2020. [DOI: 10.1016/bs.acat.2020.09.003] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/22/2022]
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