Vapor–Liquid Equilibrium of R1234yf/[HMIM][Tf2N] and R1234ze(E)/[HMIM][Tf2N] Working Pairs for the Absorption Refrigeration Cycle

The solubilities of 2,3,3,3-tetrafluoropropylene (R1234yf) and trans -1,3,3,3-tetrafluoropropene (R1234ze(E)) in 1-hexyl-3-methylimidazolium bis(trifluoromethylsulfonyl)imide ([HMIM][Tf 2 N]) were measured at temperatures from 293 to 353 K and at pressures up to 925 kPa. A comparison of the solubilities of R1234yf, R1234ze(E), and hydrofluorocarbons in [HMIM][Tf 2 N] was conducted and showed that the solubilities of R1234yf and R1234ze(E) are comparable to those of hydrofluorocarbons but more sensitive to temperature. The solubilities of R1234yf and R1234ze(E) in [HMIM][Tf 2 N] were correlated well with a modified Krichevsky–Kasarnovsky equation and the NRTL equation.