COSMO-RS Method for Screening Absorption Refrigerant Working Pairs Using Ionic Liquids as Absorbents

In this work, absorption refrigerant working pairs consisting of four HFO refrigerants, R1234ze(E), R1234yf, R1233zd, and R1243zf, and ionic liquids were studied. The different ionic liquids contained 20 cations and 16 anions. The Henry′s law constant and solubility data of working pairs were simulated by the COSMO-RS method. The differences in Henry′s law constant and solubility between the different working pairs are discussed from the perspective of polarized charge density on the molecular surface. The polarized surface charge density curve of the R1234ze(E) refrigerant has a peak in the negative region. It is compatible with anions with a peak in the positive region. However, the compatibility with the peak in the negative region is poor. Ionic liquids with low Henry′s law constants and high solubilities were screened out when they were paired with HFO refrigerants.