Method for separating and purifying carboxylic acid derived from the direct oxidation of a hydrocarbon
US6563001B1 · kind B1 · utility
Assignee
Inventors
Key dates
| Filing date | Jun 12, 2001 |
| Grant date | May 13, 2003 |
| Priority date | — |
| Expiry date | Jun 12, 2021 |
Classification
- Technology area (CPC C)Chemistry; Metallurgy
- CPC primaryC07C51/487
- WIPO fieldOrganic fine chemistry
- WIPO sectorChemistry
Abstract
The present invention relates to an improved process for processing the reaction mixture from the direct oxidation of hydrocarbon into carboxylic acid, using molecular oxygen or a gas containing it, in the liquid phase, in a solvent and in the presence of a catalyst dissolved in the reaction medium, characterized in that the said process comprises:when the composition of the reaction mixture allows it, a decantation into two liquid phases: a nonpolar upper phase and a polar lower phase;a distillation of the said lower phase or, where appropriate, of all of the reaction mixture, thus separating, on the one hand, a distillate and, on the other hand, the distillation residue comprising the acids formed, the catalyst, the heavy compounds, at least some of the solvent and, if any, the reaction intermediates and side products;a purification treatment by oxidation, using molecular oxygen or a gas containing it or using oxygen donors, of the distillation residue obtained above,a distillation of the reaction solvent and the reaction intermediates and side products which may still remain in the mixture,a crystallization of the carboxylic acid produced in the reaction;a recrystallization from…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.