Dehydration of Acetic Acid-Water Mixtures with Near Critical and Supercritical Fluid Solvents

Abstract

Equilibrium tie lines and phase densities are presented for acetic acid-water mixtures with near critical propane at 36IK and 52 bar. Experimental measurements were obtained with a static technique; the equilibrium phases were directly sampled with high-pressure liquid sample injection valves at the temperature and pressure of interest. The data obtained in this work indicate that near critical propane can be used to facilitate the production of glacial acetic acid from dilute acetic acid-water solutions. Both these experimental data and our earlier results for acetic acid-water mixtures with supercritical carbon dioxide have been used to test an equation of state which has recently been developed by Grenzheuser and Gmehling for systems which contain associating fluids. Results indicate that the equation's pure component parameters need to be refitted to represent the critical region more accurately.