Vapor-liquid equilibria for the 1,1,1-trifluoroethane (HFC-143a)+1,1,1,2-tetrafluoroethane (HFC-134a) system

Abstract

A vapor-liquid equilibrium apparatus has been developed and used to obtain data for the binary HFC-143a + HFC-134a system. Fifty-four equilibrium data are obtained for the HFC-143a + HFC-134a system over the temperature range from 263.15 to 313.15 K at 10 K intervals. The experimental data were correlated with the Carnahan-Starling-De Santis (CSD) and Peng-Robinson (PR) equations of state. Based upon the present data, the binary interaction parameters for the CSD and PR equations of state were calculated for six isotherms for the HFC-143a + HFC-134a system. The binary interaction parameters for both equations of state were fitted by a linear equation as a function of temperature. The present data were in good agreement with the calculated results from the CSD equation of state, and the deviations were less than 1.0% with the exception of two points.