Method for separating and recovering alkylene glycol monoalkyl ether, method for recycling resist composition processing waste liquid, and method for recycling resist composition processing liquid

摘要

Provided is a method for separating and recovering alkylene glycol monoalkyl ether with high purity and high yield from a solvent mixture containing alkylene glycol monoalkyl ether and its corresponding carboxylic acid ester and containing other solvents. Alkylene glycol monoalkyl ether (first solvent), alkylene glycol monoalkyl ether carboxylic acid ester (second solvent) corresponding to alkylene glycol monoalkyl ether (first solvent), alkylene glycol monoalkyl ether (first solvent) One solvent) and an alkylene glycol monoalkyl ether carboxylic acid ester by adding an alkali compound to a solvent mixture containing a solvent (third solvent) different from the alkylene glycol monoalkyl ether carboxylic acid ester (second solvent) After saponifying (second solvent) and converting it to alkylene glycol monoalkyl ether (first solvent), alkylene glycol monoalkyl ether (first solvent) is recovered by distillation.