Solubilities of CO₂, CH₄, C₂H₆, and SO₂ in ionic liquids and Selexol from Monte Carlo simulations

<p>Monte Carlo simulations are used to calculate the solubility of natural gas components in ionic liquids (ILs) and Selexol, which is a mixture of poly(ethylene glycol) dimethyl ethers. The solubility of the pure gases carbon dioxide (CO₂), methane (CH₄), ethane (C₂H₆), and sulfur dioxide (SO₂) in the ILs 1-alkyl-3-methylimidazolium bis(trifluoromethylsulfonyl)imide ([C_nmim][Tf₂N], n = 4, 6), 1-ethyl-3-methylimidazolium diethylphosphate ([emim][dep]), and Selexol (CH₃O[CH₂CH₂O]_nCH₃, n = 4, 6) have been computed at 313.15 K and several pressures. The gas solubility trend observed in the experiments and simulations is: SO₂ &gt; CO₂ &gt; C₂H₆ &gt; CH₄. Overall, the Monte Carlo simulation results are in quantitative agreement with existing experimental data. Molecular simulation is an excellent tool to predict gas solubilities in solvents and may be used as a screening tool to navigate through the large number of theoretically possible ILs.