EFFECT OF HYDROTROPES ON SOLUBILITY AND MASS-TRANSFER COEFFICIENT OF BUTYL ACETATE

This paper presents a comprehensive study on the effect of citric acid , sodium benzoate, sodium salicylate, and urea (hydrotropes) on the so lubility and mass-transfer coefficient for the extraction of butyl ace tate in water. The influence of a wide range of hydrotrope concentrati ons (0-3.0 mol/L) and different temperatures (303 K to 333 K) on the s olubility of butyl acetate has been studied. The influence of differen t hydrotrope concentrations on the mass-transfer coefficient for the b utyl acetate +water system has been ascertained. The Setschenow consta nt, K-s, a measure of the effectiveness of hydrotrope, has been determ ined for each case. The solubility of butyl acetate increases with inc rease in hydrotrope concentration and also with temperature. Consequen t to the increase in the solubility of butyl acetate, the mass-transfe r coefficient was also found to increase with increase in hydrotrope c oncentration. A minimum hydrotrope concentration was found essential t o show a significant increase in the solubility and mass-transfer coef ficient for the butyl acetate + water system. The enhancement factor, which is the ratio of the value in the presence and absence of a hydro trope, is reported for both solubility and mass-transfer coefficient.