Eastman Chemical Company

Thomas Michael Pell, Jr

Michael Paul Ekart

David Dunlap Cornell

Alan George Wonders

Robert Lin

Damon Bryan Shackelford

Gerald Charles Tustin

Mary Therese Jernigan

Donald Lee Carver

Ruairi Seosamh O'Meadhra

David Alan Jenkins

William Speight Murdoch

Leigh A Alexander

Damon Brian Shackelford

Disclosed is an optimized system for more efficiently and economically producing terephthalic acid. The system includes an oxidative digestion reactor/zone configured to provide optimized residence time distribution for the solid and liquid phases of the reaction medium processed therein.

Polycarboxylic acid production system with enhanced residence time distribution for oxidative digestion

Disclosed is an optimized system for more efficiently and economically producing terephthalic acid. The system includes an novel method for heating the slurry and/or reaction medium subjected to oxidative digestion.

Polycarboxylic acid production system with enhanced heating for oxidative digestion

A process for producing high quality TPA suitable for PET feedstock material from recycled polyester. The process includes the steps of depolymerizing the polyester to form DMT; separating the DMT from secondary materials; and hydrolyzing the DMT to form TPA. In a preferred embodiment of the invention the recycled polyester is contacted with a component monomer or oligomer thereof to liquefy the polyester prior to depolymerizing the polyester.

Process for recycling polyesters

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

Disclosed is a process for the production and purification of dialkyl naphthalenedicarboxylate compounds wherein a crude naphthalenediacarboxylic acid is esterified with an alkanol such as methanol to produce a crude esterification product comprising dialkyl naphthalenedicarboxylate, starting materials and other compounds and the crude esterification product is purified by flash distillation to remove impurities which can cause fouling of conventional distillation equipment. A particularly useful diester is dimethyl 2,6-naphthalenedicarboxylate.

Process for the preparation of dialkyl esters of naphthalenedicarboxylic acids

An apparatus for depolymerizing recycled polyester into its component ester monomers and half esters includes a first reactor for depolymerizing the recycled polyester, a separator for separating ester monomeric components and half-esters from secondary materials produced in the first reactor, and a second reactor for producing a low molecular weight polyester from liquefied separator products.

Depolymerization apparatus for recycling polyesters

A process for recovering suitable polyester feedstock material from recycled polyester includes the steps of depolymerizing the polyester into its component ester monomers and half-esters; separating the monomers and half-esters from other secondary materials; and mixing the component ester monomers and half-esters with additional monomers to produce a low molecular weight polyester. In a preferred embodiment of the invention the recycled polyester is contacted with a component monomer or oligomer thereof to liquefy the polyester before the polyester is depolymerized. The invention further provides an apparatus for carrying out the process. The apparatus includes a first reactor for depolymerizing the recycled polyester, a separator for separating ester monomeric components and half-esters from secondary materials produced in the first reactor, and a second reactor for producing a low molecular weight polyester from the liquefied separator products.

Depolymerization process for recycling polyesters

A new process is described for recycling polyesters. In accordance with the described process, postconsumer or scrap polyester is reacted with glycol to produce a monomer or low molecular weight oligomer by depolymerization of the polyester. The monomer or oligomer, as the case may be, is then purified using one or more of a number of steps including filtration, crystallization, and optionally adsorbent treatment or evaporation. The monomer or oligomer thus produced is particularly suitable as a raw material for acid or ester based polyester production of packaging grade polyester material. Because the process includes purification steps, specifications for the previously used polyester material need not be strict.

Process including glycolysis and subsequent purification for recycling

A process useful for the recovery of terephthalic acid and ethylene glycol from poly(ethylene terephthalate) or its copolymers. The process is economical, beneficial to the environment and provides polymer grade terephthalic acid and ethylene glycol from post-consumer resin. The process is a six-step process including: (1) contacting a resin containing poly(ethylene terephthalate) with water at elevated temperature and pressure, (2) cooling the resulting mixture to provide a solid portion containing terephthalic acid and a liquid portion containing ethylene glycol, (3) recovery of the ethylene glycol from the liquid portion by distillation, (4) recovery of the terephthalic acid by heating the solid portion in the presence of water vapor at elevated temperature to produce a vapor containing terephthalic acid and water, (5) cooling terephthalic acid water vapor mixture to a temperature below the dew point of terephthalic acid and (6) collecting the polymer grade terephthalic acid. The polymer grade terephthalic acid and ethylene glycol provided by this process can be used to make high quality terephthalate homopolymers or copolymers for applications including clear bottles and fibers.

Growing community of inventors

Daytona Beach, FL, United States of America

Thomas Michael Pell, Jr