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:
Oct. 21, 1997
Filed:
May. 06, 1996
Mitsubishi Gas Chemical Company, Inc., Tokyo, JP;
Toyo Boseki Kabushiki Kaisha, Osaka, JP;
Mizushima Aroma Company, Ltd., Kurashiki, JP;
Abstract
There is disclosed a process for producing terephthalic acid which comprises oxidizing in a liquid-phase a starting raw material comprising p-xylene incorporated with 3 to 35% by weight of p-tolualdehyde based on the same at a temperature in the range of 120.degree. to 240.degree. C. by means of a molecular oxygen-containing gas by using a lower aliphatic monocarboxylic acid as a solvent in the presence of a catalyst comprising a manganese compound having 50 to 1000 ppm by weight of manganese atoms, a cobalt compound having 50 to 2000 ppm by weight of cobalt atoms and a bromine compound having 100 to 4000 ppm by weight of bromine atoms, each based on the solvent. By virtue of the above specific constitution, it is made possible to produce high-quality terephthalic acid with a high residual rate of the lower aliphatic monocarboxylic acid as a solvent minimized in its loss, thereby enabling the production of high-quality polyester with high whiteness from the above terephthalic acid and a glycol.