Vapour–liquid equilibrium measurements for binary mixtures of R32, R143a, R134a and R125 with a perfluoropolyether lubricant

In the present work, vapour–liquid equilibria of four binary systems refrigerant–lubricant oil have been investigated, CF3CHF2 (R125), CF3CH2F (R134a), CF3CH3 (R143a) and CH2F2 (R32) as refrigerants and a commercial perfluoropolyether (PFPE), Fluorolink D10H, as lubricant. Vapour–liquid equilibrium data, consisting of isothermal measurement of equilibrium pressure at a fixed composition, have been correlated with an extended Flory–Huggins equation and the corresponding parameters have been determined. Good agreement has been found between experimental data and the model predictions.