Process for producing highly pure isophthalic acid
US5189209A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | May 17, 1991 |
| Grant date | Feb 23, 1993 |
| Priority date | — |
| Expiry date | May 17, 2011 |
Classification
- Technology area (CPC C)Chemistry; Metallurgy
- CPC primaryC07C51/487
- WIPO fieldOrganic fine chemistry
- WIPO sectorChemistry
Abstract
A process for producing highly pure isophthalic acid which comprises (a) carrying out liquid phase oxidation of an m-dialkyl benzene with molecular oxygen in an acetic acid solvent in the presence of a heavy metal catalyst to form crude isophthalic acid, (b) contact-treating the resulting crude isophthalic acid with a noble metal catalyst belonging to the Group VIII of the Periodic Table supported by activated carbon in the presence of hydrogen, and then (c) separating the deposited isophthalic acid crystal and (d) filtration-treating the separated mother liquor and (e) recirculating the mother liquor thus treated into the liquid phase oxidation step (a) for reusing as a solvent in step (a) is disclosed.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.