Chemical potentials of alkaline earth metal halide aqueous electrolytes and solubility of their hydrates by molecular simulation: Application to CaCl2, antarcticite, and sinjarite
We present a molecular-level simulation study of CaCl2 in water and crystalline hydrates formed by CaCl2 at ambient (298.15 K, 1 bar) conditions and at a high-temperature high-pressure state (365 K, 275 bars) typical of hydraulic fracturing conditions in natural-gas extraction, at which experimental...
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craippubl:10.1063/1.5024212 2024-06-23T07:47:15+00:00 Chemical potentials of alkaline earth metal halide aqueous electrolytes and solubility of their hydrates by molecular simulation: Application to CaCl2, antarcticite, and sinjarite Moučka, Filip Kolafa, Jiří Lísal, Martin Smith, William R. Grantová Agentura České Republiky Horizon 2020 Framework Programme 2018 http://dx.doi.org/10.1063/1.5024212 https://pubs.aip.org/aip/jcp/article-pdf/doi/10.1063/1.5024212/16672042/222832_1_online.pdf en eng AIP Publishing The Journal of Chemical Physics volume 148, issue 22 ISSN 0021-9606 1089-7690 journal-article 2018 craippubl https://doi.org/10.1063/1.5024212 2024-06-06T04:04:36Z We present a molecular-level simulation study of CaCl2 in water and crystalline hydrates formed by CaCl2 at ambient (298.15 K, 1 bar) conditions and at a high-temperature high-pressure state (365 K, 275 bars) typical of hydraulic fracturing conditions in natural-gas extraction, at which experimental properties are poorly characterized. We focus on simulations of chemical potentials in both solution and crystalline phases and on the salt solubility, the first time to our knowledge that such properties have been investigated by molecular simulation for divalent aqueous electrolytes. We first extend our osmotic ensemble Monte Carlo simulation technique [F. Moučka et al., J. Phys. Chem. B 115, 7849–7861 (2011)] to such solutions. We then describe and apply new methodology for the simulation of the chemical potentials of the experimentally observed crystalline hydrates at ambient conditions (antarcticite, CaCl2·6H2O) and at high-temperature conditions (sinjarite, CaCl2·2H2O). We implement our methodologies using for both phases the CaCl2 transferable force field (FF) based on simple point charge-extended water developed by Mamatkulov et al. [J. Chem. Phys. 138, 024505 (2013)], based on training sets involving single-ion and ion-pair low-concentration solution properties at near-ambient conditions. We find that simulations of the solution chemical potentials at high concentrations are somewhat problematic, exhibiting densities diverging from experimental values and accompanied by dramatically decreasing particle mobility. For the solid phases, the sinjarite crystalline lattice differs from experiment only slightly, whereas the simulations of antarcticite completely fail, due to instability of the crystalline lattice. The FF thus only successfully yields the sinjarite solubility, but its value m = 8.0(7) mol kg−1H2O lies well below the experimentally observed solubility range at 1 bar pressure of (12m, 15m) in the temperature interval (320 K, 400 K). We conclude that the used FF does not provide a good description of ... Article in Journal/Newspaper Antarc* AIP Publishing The Journal of Chemical Physics 148 22 222832 |
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English |
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We present a molecular-level simulation study of CaCl2 in water and crystalline hydrates formed by CaCl2 at ambient (298.15 K, 1 bar) conditions and at a high-temperature high-pressure state (365 K, 275 bars) typical of hydraulic fracturing conditions in natural-gas extraction, at which experimental properties are poorly characterized. We focus on simulations of chemical potentials in both solution and crystalline phases and on the salt solubility, the first time to our knowledge that such properties have been investigated by molecular simulation for divalent aqueous electrolytes. We first extend our osmotic ensemble Monte Carlo simulation technique [F. Moučka et al., J. Phys. Chem. B 115, 7849–7861 (2011)] to such solutions. We then describe and apply new methodology for the simulation of the chemical potentials of the experimentally observed crystalline hydrates at ambient conditions (antarcticite, CaCl2·6H2O) and at high-temperature conditions (sinjarite, CaCl2·2H2O). We implement our methodologies using for both phases the CaCl2 transferable force field (FF) based on simple point charge-extended water developed by Mamatkulov et al. [J. Chem. Phys. 138, 024505 (2013)], based on training sets involving single-ion and ion-pair low-concentration solution properties at near-ambient conditions. We find that simulations of the solution chemical potentials at high concentrations are somewhat problematic, exhibiting densities diverging from experimental values and accompanied by dramatically decreasing particle mobility. For the solid phases, the sinjarite crystalline lattice differs from experiment only slightly, whereas the simulations of antarcticite completely fail, due to instability of the crystalline lattice. The FF thus only successfully yields the sinjarite solubility, but its value m = 8.0(7) mol kg−1H2O lies well below the experimentally observed solubility range at 1 bar pressure of (12m, 15m) in the temperature interval (320 K, 400 K). We conclude that the used FF does not provide a good description of ... |
author2 |
Grantová Agentura České Republiky Horizon 2020 Framework Programme |
format |
Article in Journal/Newspaper |
author |
Moučka, Filip Kolafa, Jiří Lísal, Martin Smith, William R. |
spellingShingle |
Moučka, Filip Kolafa, Jiří Lísal, Martin Smith, William R. Chemical potentials of alkaline earth metal halide aqueous electrolytes and solubility of their hydrates by molecular simulation: Application to CaCl2, antarcticite, and sinjarite |
author_facet |
Moučka, Filip Kolafa, Jiří Lísal, Martin Smith, William R. |
author_sort |
Moučka, Filip |
title |
Chemical potentials of alkaline earth metal halide aqueous electrolytes and solubility of their hydrates by molecular simulation: Application to CaCl2, antarcticite, and sinjarite |
title_short |
Chemical potentials of alkaline earth metal halide aqueous electrolytes and solubility of their hydrates by molecular simulation: Application to CaCl2, antarcticite, and sinjarite |
title_full |
Chemical potentials of alkaline earth metal halide aqueous electrolytes and solubility of their hydrates by molecular simulation: Application to CaCl2, antarcticite, and sinjarite |
title_fullStr |
Chemical potentials of alkaline earth metal halide aqueous electrolytes and solubility of their hydrates by molecular simulation: Application to CaCl2, antarcticite, and sinjarite |
title_full_unstemmed |
Chemical potentials of alkaline earth metal halide aqueous electrolytes and solubility of their hydrates by molecular simulation: Application to CaCl2, antarcticite, and sinjarite |
title_sort |
chemical potentials of alkaline earth metal halide aqueous electrolytes and solubility of their hydrates by molecular simulation: application to cacl2, antarcticite, and sinjarite |
publisher |
AIP Publishing |
publishDate |
2018 |
url |
http://dx.doi.org/10.1063/1.5024212 https://pubs.aip.org/aip/jcp/article-pdf/doi/10.1063/1.5024212/16672042/222832_1_online.pdf |
genre |
Antarc* |
genre_facet |
Antarc* |
op_source |
The Journal of Chemical Physics volume 148, issue 22 ISSN 0021-9606 1089-7690 |
op_doi |
https://doi.org/10.1063/1.5024212 |
container_title |
The Journal of Chemical Physics |
container_volume |
148 |
container_issue |
22 |
container_start_page |
222832 |
_version_ |
1802651342097874944 |