abstract |
PROBLEM TO BE SOLVED: To provide a method for efficiently recovering a purified ester monomer from polyester fiber waste. SOLUTION: A method for recovering ester monomers from polyester fiber waste, (1) a step of depolymerizing polyester fiber waste with ethylene glycol (EG) to form an EG solution containing an ester monomer, (2) EG solution A step of filtering insoluble matter therein at a temperature exceeding 35 ° C., (3) a step of crystallizing the ester monomer by cooling the EG solution to 35 ° C. or less, and (4) a crystallized ester monomer and a liquid component Solid-liquid separation to obtain a crude ester monomer, (5) a step of dissolving the crude ester monomer in unused EG to obtain an EG solution, and (6) purification of the EG solution to obtain a purified ester monomer. A process comprising: [Selection figure] None |