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. 03, 1976
Filed:
Nov. 29, 1973
Horst-Dieter Wulf, Marl, DT;
Ferdinand List, Marl, DT;
Friedrich-August Orlowski, Haltern, DT;
Norbert Wilke, Marl, DT;
Emmerich Pflegerl, Marl, DT;
Abstract
Dimethyl terephthalate is prepared by the continuous esterification of terephthalic acid in the gas phase by evaporating solid terephthalic acid in a pre-reactor by means of a hot methanol vapor stream, conducting the gas mixture through a solid bed catalyst in a follow-up reactor, and recirculating a portion of the reaction product to the pre-reactor. After the pre-reactor the terephthalic acid dispersed in the methanol gas phase is heated and vaporized in one or more consecutive heat exchangers followed by one or more dwell period lengths and immediately heated to the esterification temperature prior to entry into the follow-up reactor.