The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Mar. 20, 2001
Filed:
Nov. 05, 1998
David Anthony Schiraldi, Charlotte, NC (US);
James Seay Brown, Atlanta, GA (US);
Karen Chandler, Houston, TX (US);
Charles Alan Eckert, Atlanta, GA (US);
Jeffrey Scott Hurley, Bartlett, TN (US);
David Rene Lamb, Alpharetta, GA (US);
Heather Patrick Lesutis, Atlanta, GA (US);
Charles Leonard Liotta, Atlanta, GA (US);
Arteva North America S.A.R.L., Zurich, CH;
Abstract
The esterification of a carboxylic or polycarboxylic acid, such as terephthalic acid, with ethylene oxide is conducted in the presence of a supercritical or near critical fluid with an esterification catalyst to form a monoester such as 2-hydroxyethylterephthalate (MHET). The monoester can be easily removed from the involatile terephthalic acid/catalyst bed by continuous extraction with supercritical fluid before subsequent reaction to the diester occurs. The esterification catalyst, such as quaternary ammonium salts, are at least substantially insoluble in the supercritical fluid and capable of withstanding prolonged exposure to elevated temperatures. The process is highly selective to formation of monoesters, and economical. The process can be modified for production of bis-esters or higher esters. The monoesters are polymerizable and can be used as monomers in the production of polyesters such as polyethylene terephthalate.