Propane/propylene separation and CO2 capture in magnetic ionic liquid [bmim][FeCl4]

Magnetic ionic liquids (MILs), combines the general properties of ionic liquid with magnetic properties, are starting to attract interest in the field of propane/propylene separation and CO2 capture. Solubility data of propane, propylene, cyclopropane and CO2 in magnetic ionic liquid 1-butyl-3-methylimidazolium tetrachloroferrate [bmim][FeCl4] at temperatures of (303, 313, 323, 333, 343) K and pressures up to 3300 kPa were determined in the present work. The relative expanded uncertainty of solubility measurement is estimated to be less than 4% with a level of confidence of 95%. The Henry's constants for the four gases in [bmim][FeCl4] and selectivity of C3H6/C3H8 in [bmim][FeCl4] were calculated. And the thermodynamic properties of solvation concerned about the Gibbs energy (ΔsolG∞), the enthalpy (ΔsolH∞) and the entropy (ΔsolS∞) of solvation were also obtained to offer knowledge for understanding the progress of gases dissolved in [bmim][FeCl4]. The experimental results were correlated with a modified KK equation and NRTL equation.