Abstract
In order to recover and reuse refrigerants that accelerate global warming, it is necessary to absorb refrigerants and separate mixed refrigerants. Therefore, this study evaluated the performances of 1-hexyl-3-methylimidazolium (HMIM)-based ionic liquids [HMIM][BF4], [HMIM][PF6], and [HMIM][Tf2N] for the selective absorption of R134a and R1234yf refrigerants. According to the experimental results, refrigerant absorption depended on the viscosity of the ionic liquid, the molecular structure and temperature of the refrigerant, and the pressure. As Henry’s law constant decreased, the refrigerant-absorption performance of the HMIM-based ionic liquids increased. In addition, [HMIM][Tf2N] and [HMIM][BF4] exhibited the highest absorption performance of refrigerants per hour at 300 and 400 kPa, respectively. R134a demonstrated better refrigerant-absorption performance than R1234yf, which indicates the possibility of selective separation using ionic liquids.
