METHOD FOR PRODUCING GLYCOLIDE, WHICH IS PROVIDED WITH RECTIFICATION STEP BY MEANS OF GAS-LIQUID COUNTERCURRENT CONTACT, AND METHOD FOR PURIFYING CRUDE GLYCOLIDE

摘要

A method for producing glycolide provided with: step (1) wherein a GAO composition, which preferably contains a high-boiling-point organic solvent or a solubilizing agent, is supplied into a reactor and heated to a temperature at which a depolymerization reaction of the GAO occurs; step (2) wherein the heating is continued to subject the GAO to the depolymerization reaction, thereby producing glycolide; step (3) wherein glycolide is distilled out of the reactor; step (4) wherein the distillate is introduced into a rectifier and is rectified by means of gas-liquid countercurrent contact; and step (5) wherein glycolide is recovered. A method for purifying crude glycolide provided with: step (i) wherein a crude glycolide composition, which preferably contains a high-boiling-point organic solvent or a solubilizing agent, is supplied into a reactor and heated so that glycolicde is distilled; step (ii) wherein the distillate is introduced into a rectifier and is rectified by means of gas-liquid countercurrent contact; and step (iii) wherein glycolide is recovered. A glycolide producing apparatus and a crude glycolide purifying apparatus, each of which is provided with a reactor and a rectifier.