Phase equilibria of CFC alternative refrigerant mixtures: 1,1,1,2,3,3,3-Heptafluoropropane (HFC-227ea)+difluoromethane (HFC-32),+1,1,1,2-tetrafluoroethane (HFC-134a), and +1,1-difluoroethane (HFG152a)

Abstract

Isothermal vapor-liquid equilibria were measured for the binary systems difluoromethane (HFC-32) + 1,1,1,2,3,3,3-heptafluoropropane (HFC-22ea) and 1,1-difluoroethane (HFC-152a) + 1,1,1,2,3,3,3-heptafluoropropane at 283.15 and 303.15K. and 1,1,1,2-tetrafluoroethane (HFC-134a)+1,1,1,2,3,3,3-heptafluoropropane at 303.15 and 323.15 K in an apparatus in which both phases were recirculated. The experimental data were correlated with the Peng-Robinson equation of state using the Wong-Sandler mixing rules. Azeotropic behavior has not been found in any of the three mixtures.