Abstract：In order to obtain proper reaction conditions of lactid synthesis,H3PW12O14-ZnO was adopted to catalyze the reaction of D,L-lactic generation from D,L-lactide.The results showed that 25.0% yield of D,L-lactide was obtained after recrystallization with ethyl acetate under the following conditions:catalyst quantity 1.2%(H3PW12O14/ZnO=2:3),dehydration pressure 2.0 kPa,dehydration-polymerization at 140 ℃ and pyrolysis-polymerization at 230 ℃.While adding 10 mL ethylene glycol as a diluent,29.4% yield of D,L-lactide was obtained after recrystallization with ethyl acetate under the same conditions.
2012, Vol. 34 
