Vapor-liquid equilibria for pure HCFCHFC substances by Gibbs ensemble simulation of Stockmayer potential molecules

A method for deriving the Stockmayer potential parameters for polar fluids from phase-coexistence data has been developed. The parameters for a polar fluid can be determined by correlations in terms of the critical temperature, the saturated liquid density and the saturated vapor pressure at a specific reduced temperature, Tr = 0.75. With the potential parameters, Gibbs Ensemble Monte Carlo (GEMC) simulations for hydrochlorofluorocarbons (HCFCs)/hydrofluorocarbons (HFCs) were carried out at different temperature. Simulated molar volumes of both the vapor and liquid phases, saturated vapor pressures, and enthalpy of vaporization are all in good agreement with the experimental data, which indicates that the so-called effective Stockmayer potential with the parameters proposed in this work is capable of predicting accurately the vapor-liquid equilibria for the environment-related HCFCHFC substances.