(443h) Vapor-Liquid Equilibrium Data for R32, R134a, and R1234ze(E) Systems over the Temperature Range from (263 to 323) K

Hydrofluoroolefins (HFOs) are of prevailing interest as they may serve as environmental-friendly alternatives to replace chlorofluorocarbons (CFCs) and hydrofluorocarbons (HFCs) in numerous applications. For the design and simulation of refrigeration systems using mixtures containing HFOs, precise knowledge of their thermophysical properties, especially vapor-liquid equilibrium (VLE) data, is essential. However, based on a literature survey, the public experimental data for R32, R134a, and R1234ze(E) systems are still limited.

For this research, a liquid-recirculation analytical apparatus was developed to carry out the measurements (FIG. 1).^[1] The VLE experimental data for the binary mixtures of R32 + R134a, R32 + R1234ze(E), R134a + R1234ze(E), and the ternary system of R32 + R134a + R1234ze(E) were obtained over the temperature range from (263 to 323) K. The standard uncertainties of the temperature and pressure measurements are 10 mK and 0.5 kPa, respectively. The standard uncertainties of both vapor and liquid phase mole fractions are estimated to be within 0.005. The binary VLE properties were correlated by the Peng-Robinson-Stryjek-Vera equation of state^[2] combined with the Wong-Sandler (WS) mixing rule and the non-random two-liquid activity coefficient model (NRTL). With the fitted parameters of binary systems from this work and the literature, the ternary VLE properties were predicted. Good agreement between the experimental data and the calculated results were obtained.

References

[1] Hu X.Z., Meng X.Y., Wu J.T., Fluid Phase Equilib. 431 (2017) 58-65.

[2] Stryjek, R., Vera, J. H., Can. J. Chem. Eng. 64 (1986) 820-826