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:
Apr. 25, 1989
Filed:
Oct. 06, 1987
Applicant:
Inventors:
Assignee:
Mitsubishi Gas Chemical Company, Inc., Tokyo, JP;
Primary Examiner:
Int. Cl.
CPC ...
C07C / ;
U.S. Cl.
CPC ...
562416 ;
Abstract
A process for producing pyromellitic acid which comprises oxidizing 2,4,5-trimethylbenzaldehyde with a gas containing molecular oxygen in the presence of a water solvent containing 0.5 to 12% by weight of bromine ion, 0.01 to 2.0% by weight of manganese ion and 0.1 to 10,000 ppm by weight of iron ion. According to the present invention, pyromellitic acid can be obtained in a high yield and, at the same time, the amount of remaining intermediate compounds such as methyltrimellitic acid and the like can be made few, so that pyromellitic acid can be purified easily.