Dielectric Properties of Aqueous Electrolyte Solutions Confined in Silica Nanopore: Molecular Simulation vs. Continuum-Based Models
Dielectric behavior of electrolyte aqueous solutions with various concentrations in a cylindrical nanopore of MCM 41 silica has been investigated. The effect of confinement is investigated by using isothermal-isosurface-isobaric statistical ensemble, which has proved to be an effective alternative t...
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MDPI AG
2022-02-01
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| Series: | Membranes |
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| Online Access: | https://www.mdpi.com/2077-0375/12/2/220 |
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| author | Haochen Zhu Bo Hu |
| author_facet | Haochen Zhu Bo Hu |
| author_sort | Haochen Zhu |
| collection | DOAJ |
| description | Dielectric behavior of electrolyte aqueous solutions with various concentrations in a cylindrical nanopore of MCM 41 silica has been investigated. The effect of confinement is investigated by using isothermal-isosurface-isobaric statistical ensemble, which has proved to be an effective alternative to the Grand Canonical Monte Carlo (GCMC) simulation method. Several single-salt solutions have been considered (e.g., NaCl, NaI, BaCl<sub>2</sub>, MgCl<sub>2</sub>) in order to investigate the effect of ion polarizability, ion size, and ion charge. The effect of salt concentration has also been addressed by considering NaCl solutions at different concentrations (i.e., 0.1 mol/L, 0.5 mol/L, and 1 mol/L). The motivation in performing this integrated set of simulations is to provide deep insight into the dielectric exclusion in NF theory that plays a significant role in separation processes. It was shown that the dielectric constant increased when ions were added to water inside the nanopore (with respect to the dielectric constant of confined pure water) unlike what was obtained in the bulk phase and this phenomenon was even more pronounced for electrolytes with divalent ions (MgCl<sub>2</sub> and BaCl<sub>2</sub>). Therefore, our simulations indicate opposite effects of ions on the dielectric constant of free (bulk) and nanoconfined aqueous solutions. |
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| id | doaj.art-e1b2a9d3213b4ed49cb39441081354fa |
| institution | Directory Open Access Journal |
| issn | 2077-0375 |
| language | English |
| last_indexed | 2024-03-09T21:28:02Z |
| publishDate | 2022-02-01 |
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| series | Membranes |
| spelling | doaj.art-e1b2a9d3213b4ed49cb39441081354fa2023-11-23T21:03:45ZengMDPI AGMembranes2077-03752022-02-0112222010.3390/membranes12020220Dielectric Properties of Aqueous Electrolyte Solutions Confined in Silica Nanopore: Molecular Simulation vs. Continuum-Based ModelsHaochen Zhu0Bo Hu1State Key Laboratory of Pollution Control and Resources Reuse, Key Laboratory of Yangtze River Water Environment, College of Environmental Science and Engineering, Tongji University, Ministry of Education, 1239 Siping Rd., Shanghai 200092, ChinaState Key Laboratory of Pollution Control and Resources Reuse, Key Laboratory of Yangtze River Water Environment, College of Environmental Science and Engineering, Tongji University, Ministry of Education, 1239 Siping Rd., Shanghai 200092, ChinaDielectric behavior of electrolyte aqueous solutions with various concentrations in a cylindrical nanopore of MCM 41 silica has been investigated. The effect of confinement is investigated by using isothermal-isosurface-isobaric statistical ensemble, which has proved to be an effective alternative to the Grand Canonical Monte Carlo (GCMC) simulation method. Several single-salt solutions have been considered (e.g., NaCl, NaI, BaCl<sub>2</sub>, MgCl<sub>2</sub>) in order to investigate the effect of ion polarizability, ion size, and ion charge. The effect of salt concentration has also been addressed by considering NaCl solutions at different concentrations (i.e., 0.1 mol/L, 0.5 mol/L, and 1 mol/L). The motivation in performing this integrated set of simulations is to provide deep insight into the dielectric exclusion in NF theory that plays a significant role in separation processes. It was shown that the dielectric constant increased when ions were added to water inside the nanopore (with respect to the dielectric constant of confined pure water) unlike what was obtained in the bulk phase and this phenomenon was even more pronounced for electrolytes with divalent ions (MgCl<sub>2</sub> and BaCl<sub>2</sub>). Therefore, our simulations indicate opposite effects of ions on the dielectric constant of free (bulk) and nanoconfined aqueous solutions.https://www.mdpi.com/2077-0375/12/2/220silica nanoporedielectric constantelectrolyte aqueous solutionsnanofiltration theorymolecular dynamics simulation |
| spellingShingle | Haochen Zhu Bo Hu Dielectric Properties of Aqueous Electrolyte Solutions Confined in Silica Nanopore: Molecular Simulation vs. Continuum-Based Models Membranes silica nanopore dielectric constant electrolyte aqueous solutions nanofiltration theory molecular dynamics simulation |
| title | Dielectric Properties of Aqueous Electrolyte Solutions Confined in Silica Nanopore: Molecular Simulation vs. Continuum-Based Models |
| title_full | Dielectric Properties of Aqueous Electrolyte Solutions Confined in Silica Nanopore: Molecular Simulation vs. Continuum-Based Models |
| title_fullStr | Dielectric Properties of Aqueous Electrolyte Solutions Confined in Silica Nanopore: Molecular Simulation vs. Continuum-Based Models |
| title_full_unstemmed | Dielectric Properties of Aqueous Electrolyte Solutions Confined in Silica Nanopore: Molecular Simulation vs. Continuum-Based Models |
| title_short | Dielectric Properties of Aqueous Electrolyte Solutions Confined in Silica Nanopore: Molecular Simulation vs. Continuum-Based Models |
| title_sort | dielectric properties of aqueous electrolyte solutions confined in silica nanopore molecular simulation vs continuum based models |
| topic | silica nanopore dielectric constant electrolyte aqueous solutions nanofiltration theory molecular dynamics simulation |
| url | https://www.mdpi.com/2077-0375/12/2/220 |
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