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1. (WO2001030729) METHOD FOR SEPARATING AND RECOVERING DIMETHYL TEREPHTHALATE AND ETHYLENE GLYCOL FROM POLYESTER WASTE

Pub. No.:    WO/2001/030729    International Application No.:    PCT/JP2000/007289
Publication Date: Fri May 04 01:59:59 CEST 2001 International Filing Date: Fri Oct 20 01:59:59 CEST 2000
IPC: C07C 29/128
C07C 67/03
C08G 63/183
C09D 167/08
Applicants: TEIJIN LIMITED

ISHIHARA, Kenichi

ISHIDA, Kenji

MIYAMOTO, Masanori

NAKASHIMA, Minoru

SATO, Kazuhiro

HASEGAWA, Hideo

Inventors: ISHIHARA, Kenichi

ISHIDA, Kenji

MIYAMOTO, Masanori

NAKASHIMA, Minoru

SATO, Kazuhiro

HASEGAWA, Hideo

Title: METHOD FOR SEPARATING AND RECOVERING DIMETHYL TEREPHTHALATE AND ETHYLENE GLYCOL FROM POLYESTER WASTE
Abstract:
A method for separating and recovering dimethyl terephthalate (DMT) and ethylene glycol (EG) from a polyester (polyethylene terephthalate (PET)) waste containing foreign matter, which comprises a step of treating a polyester waste in the EG containing a depolymerization catalyst at 175 to 190°C under 0.1 to 0.5 Mpa and removing the solid foreign matter floating on the surface of the resultant liquid reaction mixture by the flotation method, a step of removing the residual solid foreign matter from the resultant mixture by the solid-liquid separation method, a step of subjecting the resultant solution to distillation and condensation and recovering the EG having distilled out, a step of adding a transesterification catalyst and methanol to the resulting residual solution to effect a transesterification between the residual solution and methanol to thereby form DMT and EG and subjecting the resultant reaction mixture to a recrystallization treatment followed by a centrifugal separation treatment, to thereby separate the mixture into a cake of DMT and a mixed solution, and subjecting the cake to rectification to distill out and recover a high purity DMT, a step of subjecting the residual mixed solution to distillation to recover methanol, and a step of subjecting the resultant residue to distillation to recover EG.