Extraction of Ethanol from Aqueous Solutions Using Supercritical Carbon Dioxide

Abstract

The vapor-liquid equilibrium data for the carbon dioxide-ethanol-water ternary system, which are important to the study of the optimum condition of ethanol extraction from dilute aqueous solutions using supercritical carbon dioxide, were obtained. The experimental conditions of temperature and pressure were 303.2K through 363.2K and 5.6MPa through 13.2MPa, respectively. When the temperature was increased, ethanol concentration in the fluid phase increased to more than 89 mol%, which is the maximum azeotropic concentration for atmospheric distillation. The optimum extraction condition in the extraction column was examined, on the basis of vapor-liquid equilibrium data, to be a temperature in the range of 303.2K through 333.2K and a pressure of 10MPa, with the ideal temperature increasing as the ethanol concentration in the liquid phase increases. © 1989, The Society of Chemical Engineers, Japan. All rights reserved.