CPC C07C 67/54 (2013.01) [C07C 67/02 (2013.01); C07C 69/82 (2013.01); C08J 11/24 (2013.01); C08J 2367/02 (2013.01)] | 19 Claims |
1. A method for preparing a recycled raw material, which comprises:
(1) depolymerizing a waste copolyester to obtain a first reactant;
(2) removing impurities present in the first reactant to obtain a second reactant;
(3) distilling the second reactant to obtain a third reactant comprising crude recycled bis-2-hydroxyethyl terephthalate and a fourth reactant comprising a recycled diol-ester; and
(4) mixing the third reactant with an aqueous solvent and recrystallizing it to obtain a fifth reactant comprising recycled bis-2-hydroxyethyl terephthalate and a filtrate.
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