The investigation on the vapor-liquid phase equilibrium of (trifluoromethane + difluoromethane) system at temperatures ranging from (223.150 to 273.150) K

Abstract

The trifluoromethane (R23) and difluoromethane (R32) are widely used in refrigeration and chemical industry. The isothermal vapor plus liquid equilibrium (VLE) data for the R23 plus R32 system were determined experimentally at six temperatures from 223.150 K to 273.150 K. Two models were employed to regress the experimental VLE data: Peng–Robinson (PR) equation of state with the one-parameter van der Waals (vdW) mixing rule; Peng–Robinson equation of state combined non-random two-liquid (NRTL) activity coefficient model with the modified Huron-Vidal two-order (MHV2) mixing rule. The maximum average absolute relative deviation of pressure (AARDp) and average absolute deviation of vapor phase mole fraction (AADy) for PR-vdW are 2.71% and 0.0175, respectively, while the maximum AARDp and AADy for PR-MHV2-NRTL are 1.53% and 0.0148, respectively.