E.i. Dupont De Nemours and Company

Roger George Rudolph

Robert E Michel

Kamel M Makar

William Duke Everhart

Mark S Katzenberger

A process for recovering a polyester, preferably polyethylene terephthalate, from contaminated polyester waste containing non-polyester components, such as polyester blended with cotton or other fibers in fabric or fiber forms, polyester magnetic tapes, coated polyester films and engineering resins, by dissolving the polyester in molten dimethylterephthalate, methyl-p-toluate or dimethylisophthalate as solvent and separating the polyester solution from the non-polyester components. The polyester can subsequently be recovered by crystallization or the polyester solution can be used as a feedstock for methanolysis to form dimethylterephthalate (DMT) and alkylene glycol. The DMT can be subsequently hydrolyzed to recover terephthalic acid (TPA).

Recovery of polyester from contaminated polyester waste

Acetic acid is recovered from the mother liquor used to oxidize para-xylene to terephthalic acid by adding at least one organic compound having a melting point below 140.degree. C. and an atmospheric boiling point above 230.degree. C.

Recovery and recycle of acetic acid in an oxidation process

A block of dimethylterephthalate having a needle-like crystal structure. The block is easily cleavable, and has a reduced tendency to fuse to other blocks when subjected to bag-stacking pressure.

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Wilmington, NC, United States of America

Roger George Rudolph