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. 09, 1999
Filed:
Aug. 25, 1998
Fumiya Zaima, Okayama-ken, JP;
Hideaki Fujita, Okayama-ken, JP;
Masami Matsumoto, Okayama-ken, JP;
Masato Inari, Okayama-ken, JP;
Mitsubishi Gas Chemical Company, Inc., Tokyo, JP;
Abstract
A process for continuously producing an aromatic carboxylic acid comprising oxidizing an aromatic compound substituted with alkyl groups with molecular oxygen gas in the liquid phase in a solvent containing a lower aliphatic carboxylic acid in the presence of a catalyst comprising heavy metal compounds and a bromine compound, wherein a mother liquor which is obtained after removal of crystals from a reaction liquid of the liquid phase oxidation and contains heavy metal ions and bromine ion as catalyst components is brought into contact with a chelate resin of an anion exchange type to recover the catalyst components. The catalyst components are efficiently recovered, and auxiliary agents in an amount exceeding the equivalent amount and excessive labor are not necessary.