Enhanced extraction of 2,3-butanediol by medley solvent of salt and n-butanol from aqueous solution.

Enhanced extraction of 2,3-butanediol by adding salt into solvent n-butanol has been studied in this paper. Ternary phase diagrams for 2,3-butanediol + water + salt have been determined. The influences of phase ratio, type of salts and salt content on distribution coefficient and selectivity have also been investigated systematically. With phase ratio of 0.75 (w/w) and salt content of K₂HPO₄ of 25% (w/w), the distribution coefficient, separation factors and recovery yield in a single extraction process by n-butanol can reach 5.2%, 34% and 80%, respectively. Salt addition can greatly enlarge the two phase region and enhance extraction simultaneously in this system. [ABSTRACT FROM AUTHOR]