METHOD FOR PRODUCING HIGH-PURITY BIS(2-HYDROXYETHYL) TEREPHTHALATE, REGENERATED POLY(ETHYLENE TEREPHTHALATE), DECOLORING SOLVENT, AND METHOD FOR PURIFYING BIS(2-HYDROXYETHYL) TEREPHTHALATE

摘要

[Problem] To provide a method for producing high-purity bis(2-hydroxyethyl) terephthalate (BHET), by which high-purity BHET can be easily produced from colored polyester waste. [Solution] A method for producing high-purity BHET according to the present invention comprises: a depolymerization step in which colored polyester waste is depolymerized to obtain a depolymerization product including colored crude BHET; a concentration step in which low-boiling ingredients contained in the depolymerization product are removed to concentrate the BHET; a recovery step in which the BHET is recovered from the crude BHET to obtain medium-purity BHET; a crystallization separation step in which the medium-purity BHET is subjected to crystallization in a decoloring solvent and the crystals are separated, by solid-liquid separation, from the colorant-containing solvent ingredient, thereby obtaining purified BHET; and a solvent removal step in which the solvent remaining in the crystals of the purified BHET is removed to obtain high-purity BHET.