Gibbs ensemble simulation of HCFC/HFC mixtures by effective Stockmayer potential

Vapor–liquid equilibria for four HCFC/HFC binary mixtures, R22/R152a, R22/R142b, R22/R134a, and R22/R32, were simulated by using the Gibbs ensemble Monte Carlo method. The effective Stockmayer potential proposed by the authors was used to represent molecular interactions. The potential parameters for the pure substances of interest were determined from their critical temperatures, the saturated liquid densities and the saturated vapor pressures at a specific reduced temperature, Tr=0.75. The Lorenz–Berthelot combining rules were adopted to calculate the LJ parameters for unlike molecules. Phase properties for the four systems, including compositions and densities of the coexisting vapor and liquid phases were simulated, and compared with experimental data. Good results show that our method is a predictive tool for the description of phase behavior for HCFC/HFC binary systems, which are possible alternatives for CFCs.