Solubility and miscibility gap in refrigerants + lubricant, mixture of refrigerants + Ionic liquids, and hydrofluoroolefins + natural refrigerants systems: UNIFAC parameterization and solvation free energy calculations.

Natural refrigerants, low-GWP synthetic F-gas and mixtures in contact with lubricating oils in commercial air or heat-pumps were selected to study mutual solubility and miscibility in the temperature range from 248.15 K to 353.15 K. Due to restriction from F-gas regulation 2024 of the European commission (https://climate.ec.europa. eu), stress was put on the natural refrigerants and an industrial compressor oil. UNIFAC parameterization based on available experimental data was performed for systems comprising POE oils, HCFC, HFC, HFO, hydrocarbon, CO2, and ionic liquids. Also, it has been shown that the UNIFAC parameters developed in this study can readily be applied to the selective separation of refrigerant mixtures using Ionic Liquids. Molecular dynamics (MD) simulations of solvation free energy support the selectivity of ILs.