WATER-ENHANCED SOLVATION OF ORGANIC SOLUTES IN KETONE AND ESTER SOLVENTS

Previous research has shown that the solubilities of dicarboxylic acid s in certain electron-donor solvents are substantially increased in th e presence of water. Information on solubilities, liquid-liquid equili bria and maximum-boiling ternary azeotropes was screened so as to iden tify other systems where codissolved water appears to enhance solvatio n of organic solutes in solvents. Several carboxylic acids, an alcohol , diols, and phenols were selected for examination as solutes in keton e and ester solvents. Effects of water upon solute solubilities and vo latilities were measured. Results showed that water-enhanced solvation is greatest for carboxylic acids. Solute activity coefficients decrea sed by factors of 2-3,6-8, and 7-10 due to the presence of water for m ono-, di- and tricarboxylic acids, respectively. Activity coefficients decreased by a factor of about 1.5 for ethanol and 1,2-propanediol as solutes. Water-enhanced solvation of phenols is small, when existent.