Monte Carlo Simulations of Gas Solubility in the Ionic Liquid 1-n-Butyl-3-methylimidazolium Hexafluorophosphate

Abstract

The Henry's constants of water, carbon dioxide, ethane, ethene, methane, oxygen, and nitrogen are computed in the ionic liquid 1-n-butyl-3-methylimidazolium hexafluorophosphate ([bmim][PF(6)]) using test particle insertion and expanded ensemble Monte Carlo methods. The partial molar enthalpy and partial molar entropy of solvation are also computed for water, carbon dioxide, and oxygen. The results from the simulations are compared against experimental data from the literature. In addition, the accuracy and precision of the two methods in determining the Henry's constant are examined. Local organization of the ionic liquid around a solute molecule is analyzed, and the interactions responsible for the experimentally observed solubility trends are identified.

Multi-scale Modeling of Structure, Dynamic and Thermodynamic Properties of Imidazolium-based Ionic Liquids: Ab initio DFT Calculations, Molecular Simulation and Equation of State Predictions

“…One block average is the average over 6000 insertions of "test" molecules in one configuration. The relative errors are around 20% which is a typical value for the Widom's test particle insertion method and is in accord with errors reported for the simulation of gas solubilities in IL [27,28,46].…”

“…Subsequent work concentrated on the simulation of solubilities of gases (such as CO 2 , CO, etc.) and water in IL [27][28][29]. In most cases, imidazolium-based ILs were examined, which are considered as first-generation ILs.…”

Molecular models for 267 binary mixtures validated by vapor–liquid equilibria: A systematic approach

“…Several authors used them as solute models for predictions of the Henry's law constant: Boutard et al [15] for O 2 in ethanol, Krishnamurthy et al [16] for N 2 and O 2 in ethylene oxide and Shah and Maginn [17] for C 2 H 6 and C 2 H 4 in an ionic liquid. Grimm et al [18] used the CH 2 I 2 model to investigate local density effects on photoinduced isomerization kinetics of this substance in supercritical CO 2 .…”

The simulation of imidazolium-based ionic liquids†

“…[9,10] The force fields, now tested on the neat liquids, have begun to be used to explore interfacial [25,47,49] and solvation phenomena. [50,53,62] Most recently ab-initio MD methods have been used to examine the neat ionic liquid [C 1 C 1 im]Cl. [18][19][20] The extension of the force fields to treat mixed systems has highlighted some deficiencies, [16,22] particularly in regard to charge transfer effects.…”