Isothermal vapor-liquid equilibria, excess molar volume and the deviation of refractive indices for binary mixtures of 1-butanol, 1-hexanol, 3-methyl-1-butanol and butyl acetate

Experimental vapor-liquid equilibrium (VLE) data and mixture properties are reported toward developing a process for the separation of the traditional ABE (acetone + butanol + ethanol) fermentation. Isothermal VLE measurements at 343.2 K were performed by using headspace gas chromatography (HSGC) for binary systems {1-butanol + 3-methyl-1-butanol}, {1-butanol + 1-hexanol}, {butyl acetate + 3-methyl-1-butanol}, {butyl acetate + 1-hexanol} and (3-methyl-1-birtanol + 1-hexanol). The experimental VLE binary data were correlated using the Wilson, NRTL and UNIQUAC activity coefficient model equation. In addition, a digital vibrating tube densimeter and precision digital refractometer were used to determine the excess molar volume (V-E) and the deviation of the refractive indices (Delta R) for the same binary systems at 298.2 K. The Redlich-Kister equation was employed to show that the determined V-E and Delta R data were well correlated. (C) 2017 Elsevier B.V. All rights reserved.