Liquid-Liquid Equilibria for Water + 2,3-Butanediol + 3-Methyl-1-Butanol at Different Temperatures of 303.15,313.15, and 323.15 K

Abstract

Liquid-liquid equilibria of water + 2,3- butanediol+3-methyl-1-butanol at different temperatures of 303.15, 313.15, and 323.15 K were measured. Complete phase diagrams were obtained by evaluating the solubility and tie- line results for ternary system. The consistency of the tie-line was ascertained using Othmer-Tobias plot. The effect of temperature on distribution coefficient and selectivity of 2,3- butanediol were studied. It was observed that increase in temperature has a favorable effect on the distribution coefficient and selectivity. 2,3-butanediol is promising chemical which have a wide range of applications and can be biologically produced. The separation of this diol from fermentation broth makes more than 50% of the total costs in their microbial production. It is argued that separation technologies such as aqueous two- phase extraction with short chain alcohols deserve more attention. Sharma et. al (1) investigated extraction using 3- methyl-1-butanol, butane-1-ol, 2-methyl-2-pentanone, trybutyl phosphate and butyl acetate. It has been found that solvents having good extracting power for 2,3-butanediol have a low selectivity. Therefore an investigation was carried out to study the effect of different temperatures on the selectivity , extracting power of the solvent and tie lines . This work measurement of liquid-liquid equilibrium (LLE) data of water + 2,3-butanediol + 3-methyl-1-butanol under atmospheric pressure and at different temperature ranges of 303.15, 313.15, and 323.15 K and the consistency of the tie-line was ascertained using Othmer-Tobias plots. II. MATERIALS AND METHODS: 3-methyl-1-butanol was of analytical grade and was used without further purification. 2,3-butanediol was obtained from Merk with a purity of 98% and used as such. Double distilled water was sued through out the experimental study. BD was determined by gas chromatography (Perkin Elmer Sigma 3b) using chromosorb 101 coated with 3% ffap. III. EXPERIMENTAL METHODS: Experimental section; The mutual solubilities for water + 2,3-butanediol + 3- methyl-1-butanol at different temperature ranges of 303.15,