Modelling of Liquid–liquid Equilibria in Quasi-seven-component Systems with Deep Eutectic Solvents as Extraction Media

Abstract

Liquid-liquid equilibria were experimentally investigated in systems in which the first component was aliphatic (n-hexane, n-heptane or i-octane) or aromatic hydrocarbon (toluene), the second component was pyridine or thiophene, and the third quasi-component was DES consisting of choline chloride and glycerol or choline chloride and ethylene glycol, at 25 degrees C and atmospheric pressure. The equilibria were successfully described by the NRTL and UNIQUAC models. The same models were successfully applied to describe the liquid-liquid equilibria in quasi-seven-component systems that comprised all the mentioned low molecular weight components and one DES. The restrictions of the models were discussed; it seems that the preference can be given to the UNIQUAC model.