Modeling the Vapor-Liquid equilibria of binary and ternary systems comprising associating and non-Associating compounds by using Perturbed-Chain Statistical association fluid Theory. Part I

Abstract

Perturbed-Chain Statistical Associating Fluid Theory (PC-SAFT) was implemented for modeling the vapor–liquid equilibrium of binary and ternary systems of carbon dioxide (CO2) + fatty oil, CO2 + ionic liquids (IL), CO2 + perfluoroalkanes, CO2 + HFE-449mec-f, CO2 + water + IL, CO2 + thiophene, and alcohols + thiophene at temperatures between 298.15 and 543.15 K and at pressures up to 200 bar. ILs studied in this work contain 1-octyl-3-methylimidazolium hexafluorophosphate [OMIM][PF6] and N-methyl-2-hydroxyethylammonium propionate [m-2HEA][Pr]. The PC-SAFT pure-component parameters were fitted to the experimental density and vapor pressure data of pure-components. For ILs, only liquid density data were used to obtain pure-IL PC-SAFT parameters, because of the negligible values of the vapor pressure of ILs. Temperature-dependent binary interaction parameters of the binary and ternary systems were fitted to vapor–liquid equilibrium data taken from experimental literature data. These parameters were then used to describe the VLE of other binary and ternary systems. Correlation results of the PC-SAFT were found to be in qualitative agreement with the available experimental data and improved the modeling accuracy of past models in the literature. The overall value of the absolute average relative deviation in pressure (ARDP) and vapor-phase mole fraction (ARDy) of 12.05% and 6.13%, respectively, reveals the goodness of the developed models for modeling the phase behavior of other associating or non-associating mixtures with the same parameters reported in this work.