Journal of Chemical Thermodynamics, Vol.43, No.3, 505-510, 2011
Experimental measurement of vapor pressures and (vapor plus liquid) equilibrium for {1,1,1,2-tetrafluoroethane (R134a) + propane (R290)} by a recirculation apparatus with view windows
The saturated vapor pressures of 1,1,1,2-tetrafluoroethane (R134a) and propane (R290), and the (vapor + liquid) equilibrium (VLE) data at (255.000, 265.000, 275.000, and 285.000) K for the (R134a + R290) system were measured by a recirculation apparatus with view windows. The uncertainty of the temperatures, pressures, and compositions are less than +/- 5 mK, +/- 0.0005 MPa, and +/- 0.005, respectively. The saturated vapor pressures data were correlated by a Wagner type equation and compared with the reference data. The binary VLE data were correlated with the Peng-Robinson equation of state (PR EoS) incorporating the Huron-Vidal (HV) mixing rule utilizing the nonrandom two-liquid (NRTL) activity coefficient model. For mixtures, the maximum average absolute relative deviation of pressure is 0.15%, while the maximum average absolute deviation of vapor phase mole fraction is 0.0045. Azeotropic behavior can be found for the (R134a + R290) system at measured temperatures. (C) 2010 Elsevier Ltd. All rights reserved.
Keywords:Saturated vapor pressures;(Vapor plus liquid) equilibrium;1,1,1,2-Tetrafluoroethane;Propane