1988 Volume 21 Issue 2 Pages 129-134
For the separation of fusel oil from low-concentration fermentation broths, ternary liquid-liquid equilibria at 323.2 K were measured for the systems of water and 1, 1-difluoroethane with alcohols (l-propanol, 1-butanol and 1-pentanol). The liquefied gas 1, 1-difluoroethane can achieve much higher distribution coefficients of l-propanol, 1-butanol and 1-pentanol than ethanol. Therefore, 1-propanol, 1-butanol and 1-pentanol will be selectively removed from low-concentration ethanol aqueous solutions with liquefied 1, 1-difluoroethane at low solvent ratios.
The liquid-liquid equilibrium data were correlated by the UNIQUAC and NRTL equations. The UNIQUAC equation gave better correlation of the experimental data than did the NRTL equation. However, the two-phase regions estimated by the UNIQUAC equation were larger than the experimental results for the systems of water + 1-propanol + 1, 1-difluoroethane and water + 1-pentanol + 1, 1-difluoroethane.