Process for preparing 2,6-naphthalene-dicarboxylic acid
US5183933A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Oct 15, 1991 |
| Grant date | Feb 2, 1993 |
| Priority date | — |
| Expiry date | Oct 15, 2011 |
Classification
- Technology area (CPC C)Chemistry; Metallurgy
- CPC primaryC07C51/265
- WIPO fieldOrganic fine chemistry
- WIPO sectorChemistry
Abstract
Provided is a continuous process for producing 2,6-naphthalenedicarboxylic acid by the liquid phase oxidation of 2,6-dimethylnaphthalene comprising continuously adding to a reaction zone the oxidation reaction components comprising 2,6-dimethylnaphthalene, a source of molecular oxygen, a solvent comprising an aliphatic monocarboxylic acid, and a catalyst comprising cobalt, manganese and bromine components, wherein the atom ratio of manganese to cobalt is about 5:1 to about 0.3:1, the total of cobalt and manganese is at least about 0.40 weight percent based on the weight of solvent, and maintaining the contents of the reaction zone at a temperature of about 370.degree. F. to about 420.degree. F. and at a pressure sufficient to maintain at least a portion of the monocarboxylic acid in the liquid phase thereby oxidizing the 2,6-dimethylnaphthalene to 2,6-naphthalenedicarboxylic acid. By operating according to the process of this invention, 2,6-naphthalenedicarboxylic acid can be continuously produced in high yield and with low levels of impurities.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.