Vapor-liquid equilibria of CFC alternative refrigerant mixtures: Trifluoromethane (HFC-23) plus difluoromethane (HFC-32), trifluoromethane (HFC-23) plus pentafluoroethane (HFC-125), and pentafluoroethane (HFC-125) plus 1,1-difluoroethane (HFC-152a)

Isothermal vapor-liquid equilibria for three binary mixtures of CFC alterna tive refrigerants were determined ill an equilibrium apparatus in which bot h phases were continuously recirculated, The pressures and vapor and liquid compositions were measured for the binary systems trifluoromethane (HFC-23 )+difluoromethane (HFC-32) and trifluoromethane (HFC-23)+pentafluoroethane (HFC-125) at 283.15 and 293.15 K and pentafluoroethane (HFC-125); 1,1-diflu oroethane (HFC-152a) at 293.15 K. The experimental data were correlated wit h the Peng-Robinson-Stryjek-Vera equation of state using the Huron-Vidal or iginal mixing rule. Calculated results with this equation showed good agree ment with the experimental data.