High pressure multiphase equilibria in the ternary system carbon dioxide-water-1-propanol

Abstract

Publisher Summary Ternary high-pressure equilibria in systems of gas–water–polar solvent are encountered in the supercritical extraction of products from aqueous solutions with carbon dioxide and a polar entrainer or in supercritical fluid chromatography. At elevated pressures, the phase behavior of such ternary systems can be very complex. High-pressure multiphase equilibria can be used for the recovery of alcohols and organic acids from aqueous solutions, but there are also other applications such as the extractions of fermentation products from diluted brothes. Pressure–temperature diagrams offer a useful way to depict the phase behavior of multicomponent systems in a very condensed form. This chapter presents a classification of the different types of phase behavior and thermodynamic methods to model the complex phase behavior with cubic equations of state. The qualitative phase behavior of the carbondioxide–water–1-propanol system is discussed for the temperatures 303 and 333 K.