METHOD FOR PRODUCING LACTIC ACID AND POLYLACTIC ACID

摘要

Lactic acid crystals of high purity which have excellent solid liquid separation properties can be stably produced by performing a step of passing a lactic acid-containing aqueous solution through a nanofiltration membrane and recovering the same from the permeate side and a step of distilling the lactic acid aqueous solution and recovering the same from the steam side before a step of crystallizing the lactic acid and recovering purified lactic acid crystals. A polylactic acid which has excellent physical properties can be obtained by producing the polylactic acid with the obtained lactic acid as a raw material.