Prediction of vapor-liquid equilibrium and pvTx properties of mixtures containing HFOs, HFCs, HCs, and CO2 using polar PC-SAFT model

Abstract

In this work, the polar perturbation chain statistical associated fluid theory (PC-SAFT) was utilized to determine model parameters of HFOs pure working fluid. Subsequently, a predictive equation for the binary interaction parameters of mixtures containing HFOs was constructed, allowing for the prediction of the vapor-liquid equilibrium (VLE) and pressure-volume-temperature-composition (pvTx) properties of mixtures comprising of HFOs, HFCs, HCs, and CO2. For 9 pure working fluids of HFOs, the average deviations of the polar PC-SAFT model in calculating saturated vapor pressure, saturated liquid phase density, and saturated vapor phase density were 1.2 %, 0.7 %, and 0.9 %, respectively. For the VLE properties of 35 binary mixtures containing HFOs, the average absolute relative deviation of pressure (AARD(p)) and average absolute deviation of vapor phase compositions (AAD(y)) predicted by the polar PC-SAFT were 2.4 % and 0.008, respectively. When directly using the parameters of binary subsystems to predict the VLE properties of ternary mixtures by the polar PC-SAFT model, the predicted AARD(p) and AAD(y) were 2.2 % and 0.011 for 8 ternary mixtures containing HFOs. For the pvTx properties, the predicted average absolute relative deviation of density (AARD(ρ)) was 0.9 % for 12 liquid binary mixtures containing HFOs, and the AARD(ρ) was 1.3 % for 16 vapor binary mixtures containing HFOs. The model established in this work has good predictive effects on the VLE and pvTx properties of binary mixtures containing HFOs, and can also be extended to multicomponent mixtures.