Vapor-Liquid Equilibria for the Ternary System CO2 + Ethanol + n-Hexane

Phase equilibria of multicomponent systems containing carbon dioxide + hydrocarbons are important for separation processes in petrochemical and chemical industries. Carbon dioxide in combination with alcohols is a suitable supercritical solvent + cosolvent mixture.

In this work, experimental vapor-liquid equilibrium for the ternary system CO₂ + ethanol + n-hexane were measured isothermally from subcritical up to near critical pressures. An apparatus based on the static-analytic method was used to measure the vapor–liquid equilibria for the studied system from 313 to 373 K. VLE data were correlated with the Peng–Robinson equation of state using the classical mixing rules.