LACTIDE SYNTHESIS METHOD AND LACTIDE SYNTHESIS APPARATUS

摘要

PROBLEM TO BE SOLVED: To reduce the water concentration in a lactide in a lactide synthesis apparatus or process.;SOLUTION: After a lactic acid oligomer discharge valve 10 is closed, lactic acid is transferred to a lactic acid condensation apparatus 2. The lactic acid is concentrated and condensed by heating in a vacuum, and the formed water is evaporated. Lactic acid, a lactic acid oligomer, and lactide are removed from or returned to the formed gas by means of a condensation apparatus 11. The water concentration of the gas is measured with a pressure measurement device 12. After confirming that the water concentration is not higher than a specified value, the lactic acid oligomer discharge valve 10 is opened to transfer the lactic acid oligomer. The oligomer is depolymerized to form gaseous lactide, which is then condensed and recovered.;COPYRIGHT: (C)2005,JPO&NCIPI