| 摘要 |
<p>PROBLEM TO BE SOLVED: To provide a recovering method of DMT and EG having a quality usable as a raw material of a polymer from a polyester waste comprising a polyester mixture containing at least polybuthylene terephthalate. SOLUTION: The recovering method of valuable components from a polyester waste comprises depolymerization reacting the polyester waste comprising the polyester mixture containing at least polybuthylene terephthalate in the presence of a depolymerization catalyst using ethylene glycol at 180-300 deg.C, removing tetrahydrofuran and water which occur by converting a 1,4-butanediol skeleton while the depolymerization reaction is performed, then substitution esterifying reactants in the presence of a substitution esterification catalyst using methyl alcohol, and further separating and purifying the resulting products to recover the dimethyl terephthalate and the ethylene glycol.</p> |
