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:
Aug. 13, 1996
Filed:
Jan. 03, 1995
Jacques Benzaria, Chambly, FR;
Francois Dawans, Bougival, FR;
Bruno Durif-Varambon, Vienne, FR;
Jean-Bernard Gaillard, St. Martin D'Heres, FR;
Institut Francais du Petrole, Rueil Malmaison, FR;
Abstract
An improved method for recovery of alkali metal or alkaline-earth metal terephthalate and of alkylene glycol, from polyalkylene terephthalate, in particular from polyethylene terephthalate (P.E.T.), alkylene glycol, in particular ethylene glycol produced in the form of vapor during the saponification reaction, initiated by the action of intensive kneading of polyalkylene terephthalate and the alkaline reagent at a temperature of 100.degree. to 200.degree. C. The alkylene glycol is recovered in gaseous form by entrainment by an inert gas or by extraction under low pressure. The alkaline terephthalate or alkaline-earth terephthalate is obtained in solid or powder form; it can easily be stored, transported and redissolved, in order to be purified and possibly transformed into terephthalic acid or ester.