Comparison of CP-PC-SAFT and CS-SAFT-VR-Mie in Predicting Fluid Phase Behavior in Systems of Phenolic Compounds, Aromatic Amines, Acetophenone, and Benzaldehyde

This study compares the capabilities of the Critical Point-based Revision of PC-SAFT (CP-PC-SAFT) and the Corresponding States-based SAFT of Variable Range and Mie Potential (CS-SAFT-VR-Mie) to simultaneously predict VLE, LLE and critical data available for 74 binary systems of phenol, m-cresol, 2-methoxyphenol, 2-phenylethanol, 2-ethylphenol, pyridine, aniline, benzylamine, o-toluidine, acetophenone, and benzaldehyde with nitrogen, carbon monoxide, methane, ethane, propane, n-alkanes, iso-alkanes, and other hydrocarbons. For both models, the universal k₁₂ values adjusted to the VLE data of the system propane(1)-phenol(2) were applied. It was found that these models yield comparable and, in most cases, accurate estimations of vapor pressures and the pure compound saturated liquid densities. However, CP-PC-SAFT is superior in predicting the high-pressure density and sound velocity data. CS-SAFT-VR-Mie is able to predict the VLE data fairly accurately in most of the considered cases. However, it establishes an unrealistic transitional behavior from Type I to Type II via Type VI, which seriously affects its predictions of LLE. CP-PC-SAFT exhibited better overall reliability. In particular, in most cases. it is superior in estimating VLE and yields reasonably accurate predictions of the upper critical solution temperatures. According to the global analysis performed in this study, these results could probably be attributed to the obeying of the pure compound T_c and P_c. At the same time, CP-PC-SAFT systematically underestimates the widths of the LLE phase splits and, as a result, yields inaccurate predictions of the alkane-rich phases.