Eastman Chemical Company

William Speight Murdoch

Michael Paul Ekart

Larry Cates Windes

Thomas Lloyd Yount

Paul Keith Scherrer

Thomas Michael Pell, Jr

Christopher Scott Slaughter

A process for forming reactants useful in the manufacture of polyethylene terephthalate includes the steps of: (a) contacting recyclable polyethylene terephthalate with ammonium hydroxide whereby a mixture of ammonium terephthalate and ethylene glycol is formed, (b) separating the ammonium terephthalate, and (c) heating said ammonium terephthalate at a temperature from about 225&deg; C. to about 300&deg; C. to produce terephthalic acid.

Production of terephthalic acid and ethylene glycol from polyethlene terephthalate by ammoniolysis

Recycling of polyethylene terephthalate with regeneration of acetic acid

Disclosed herein is a process for depolymerizing and purifying contaminated post-consumer polyester. In the process, depolymerization is effected by way of glycolysis in an agitated reactor vessel. The process includes the steps of contacting a contaminated polyester with an amount of a glycol to provide a molar ratio of greater than about 1 to about 5 total glycol units to total dicarboxylic acid units at a temperature between about 150 to about 300&deg; C. and an absolute pressure of about 0.5 to about 3 bars. This reaction is conducted for a time sufficient to produce, in the reactor, an upper layer having a relatively low density contaminant floating on top of a lower layer which includes a relatively high density depolymerized oligomer of the polyester, and separating the upper layer from the lower layer. The layers may be separated by removing the upper layer from the reactor in a first stream and removing said lower layer from the reactor in a second stream.

Glycolysis process for recycling of post-consumer pet

Growing community of inventors

Kingsport, TN, United States of America

William Speight Murdoch