Abstract: Centrifugal molecular distillation equipment was employed for refining lactic acid. The effects of temperature and rotary speed of evaporating plate，distance from evaporating plate and temperature difference on the purity and yield of L-lactic acid were studied. The results indicated that the optimal conditions to refine L-lactic acid by centrifugal molecular distillation were obtained at the pressure of 0.1Pa，feed-in temperature of 50—70℃，evaporating temperature at 60—75℃，rotary speed of the evaporating plate of 700—900 r/min，distance from the evaporating plate of 20—30 mm and temperature difference of 40—45℃.The purity of L-lactic acid increased from 80% to 95%，accompanied by the yield of 70% under the optimized conditions.

摘要： 以发酵液中的乳酸为原料，采用离心式分子蒸馏设备进行精制。研究了离心式分子蒸馏设备的蒸发面温度、蒸发面转速、冷热面间距、冷热面温差对L-乳酸纯度和收率的影响，试验结果表明利用离心式分子蒸馏设备精制发酵L-乳酸的最适工艺条件为：压力0.1Pa，进料温度50～70℃，蒸发面温度60～75℃，蒸发面转速700～900 r/min，冷热面间距20～30 mm，冷热面温差40～45℃，在此条件下操作L-乳酸的纯度由80%提高到95%，收率为70%。