Vapor-liquid equilibrium modeling for binary system of R152a/R1234ze(E)

Abstract

At present, the environment impact of refrigerants has been given attention. The binary mixture R152a/R1234ze(E) is an environmentally friendly refrigerant, which solves problems of poor cooling performance of the R1234ze(E) cycle and flammability of R152a. In order to obtain its basic thermal and physical parameters, it is necessary to carry out vapor–liquid equilibrium (VLE) research, and the cubic equation of states (EOS) is often used in the calculation of the thermodynamic properties of mixtures. In this paper, the VLE predicted models for R152a/R1234ze(E) in the temperature range of 298.15–328.15 K were constructed using Soave-Redlich-Kwong (SRK), Peng-Robinson (PR) equations of state (EOS) combined with van der Waals (vdW), Huron-Vidal (HV) mixing rules, respectively. The equilibrium pressures and vapor-phase mole fractions of the models were obtained by calculation, and all four models presented an extreme correlation with the experimental data. And it can be concluded that the calculated results of the PR + HV model are closer to the experimental data than those of the other three models, with the average absolute deviation of 0.0027 for vapor-phase mole fraction (AAD(ycal)) and the average absolute relative deviation of 0.243% for equilibrium pressure (AARD(pcal)), which provides a basis for accurately calculating the thermophysical properties of the mixture R152a/R1234ze (E).