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. 24, 1982
Filed:
Sep. 18, 1980
Applicant:
Inventors:
Gerhart Hoffmann, Niederkassel-Ranzel, DE;
Rudolph Cordes, Niederkassel-Ranzel, DE;
Wolfgang Merkel, Niederkassel, DE;
Assignee:
Dynamit Nobel Aktiengesellschaft, Troisdorf, DE;
Attorney:
Primary Examiner:
Assistant Examiner:
Int. Cl.
CPC ...
C07C / ;
U.S. Cl.
CPC ...
560 99 ; 2524 / ; 252463 ; 252471 ; 560 77 ; 562412 ; 562414 ;
Abstract
A process for the preparation of dimethyl terephthalate by the oxidation of p-xylene/methyl p-toluate mixtures, preferably with air, esterification of the resulting acid products, and recycling of the methyl p-toluate to the oxidation stage, employs an oxidation catalyst consisting of a combination of cobalt and manganese compounds. The concentration of manganese (Mn.sup.++) ranges between about 0.0001% and about 0.005% by weight.