Synthesis of butyl lactate using polyamine resin as catalyst under microwave heating

Esterification of lactic acid and butyl alcohol was studied,in which polyvinyl chloride-polyethylene polyamine( PVC-PP) resin was used as catalyst and heating was conducted with microwave irradiation. The effects of microwave irradiation power,irradiation time,mole ratio of the starting materials,chemical structure of the butyl alcohol and dosage of the catalyst on the reaction were discussed. Results showed that the ester yield achieves 96. 5% under conditions as amount of n-butyl alcohol 0. 24 mol,amount of lactic acid 0. 08 mol,dosage of the catalyst 0. 5 g,power of the microwave 400 W and irradiation time 12 min. The catalyst can be used for five times without significant reduction of the product yield.