Integrated process for the production of 2, 6-naphthalene dicarboxylic acid
US6448436B1 · kind B1 · utility
Assignee
Inventors
Key dates
| Filing date | Aug 22, 2000 |
| Grant date | Sep 10, 2002 |
| Priority date | — |
| Expiry date | Aug 22, 2020 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY02P20/10
- WIPO fieldOrganic fine chemistry
- WIPO sectorChemistry
Abstract
Disclosed is an integrated process for producing 2,6-naphthalene dicarboxylicacid comprising oxidizing a methylnaphthalene feedstock, hydrodebrominating the crude naphthoic acid product under conditions different from any work known in the art, forming a potassium salt of the acid; disproportionating the potassium salt to produce 2,6 potassium salts of NDA; selectively precipitating K2NDA; selectively precipitating the monopotassium salt of 2,6 NDA(KHNDA); disproportionating the KHNDA into 2,6 NDA and K2NDA; further reacting the 2,6 NDA in a pipe reactor; and drying the product 2,6 NDA by conventional means or directly slurrying directly into a PEN process. The process can tolerate impurities in the economical methylnaphthalene feed and the resulting 2,6 NDA is of high quality with <50 ppm potassium.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.