Solubility behavior of CO2 and H2S in 1-benzyl-3-methylimidazolium bis (trifluoromethylsulfonyl)imide ionic liquid

The solubility of CO2 and H2S in 1-benzyl-3-methylimidazolium bis(trifluoromethylsulfonyl)imide ([Bzmim][Tf2N]) ionic liquid has been measured at temperatures from (303.15 to 343.15) K and pressures of up to about 3.1 and 1.6 MPa, respectively. The molar volume of the gas saturated liquid phase has also been measured. It was found that the solubility of H2S in [Bzmim][Tf2N] is>2 times that of CO2. Henry's constants, partial molar volumes and partial molar thermodynamic functions at infinite dilution for dissolution of CO2 and H2S in [Bzmim][Tf2N] were evaluated from the experimental data. The experimental data was correlated using the extended Henry's law combined with a simplified Pitzer's model. The experimental data was further correlated by a generic Redlich-Kwong equation of state (GRK EoS). Both models show quite good correlative accuracy for CO2/H2S + [Bzmim][Tf2N] mixtures. However, the former model was superior to that of the GRK EoS for H2S + [Bzmim][Tf2N]. (C) 2021 Elsevier Ltd.

Automated summary

The solubility of CO2 and H2S in 1-benzyl-3-methylimidazolium bis(trifluoromethylsulfonyl)imide ([Bzmim][Tf2N]) ionic liquid has been measured, and their thermodynamic properties in the ionic liquid have been evaluated. The results show that H2S has a significantly higher solubility than CO2.