Microwave assisted enzymatic esterification of lactic acid and ethanol in phosphonium type ionic liquids as co-solvents

Microwave heating was found to have a beneficial effect on the enzymatic esterification of lactic acid (LA) with ethanol in Cyphos 202 ionic liquid (IL) medium. Microwave irradiation caused hydrolysis of lactoyllactic acid (the linear dimer of LA) during the reaction, thus, as a result, more lactic acid was available as substrate and a higher ester yield was achieved in the esterification.