To obtain terephthalic acid and an alkylene glycol in high purities as split products using a polyalkylene terephthalate-treated product as feedstock which is obtained by efficiently removing metal(s) from polyalkylene terephthalate wastes containing the metal(s) derived from esterification and/or polycondensation catalyst(s).
A treating method is provided, comprising retrieving polyalkylene terephthalate-based wastes generated from commercial polyalkylene terephthalate-based products and/or in the process of producing the products and recovering effective ingredients. Specifically, this method comprises the following procedure: The polyalkylene terephthalate wastes are charged into an alkylene glycol followed by agitation under heating at 100-180°C to selectively dissolve into the alkylene glycol metal compound(s) derived from the esterification and/or polycondensation catalyst(s) contained in the system to remove the metal compound(s).
IMAGAWA MASAO
HIRAOKA SHOJI
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