Removal of iodine or iodide impurities
US4975155A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | Sep 19, 1989 |
| Grant date | Dec 4, 1990 |
| Priority date | — |
| Expiry date | Sep 19, 2009 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY10S203/06
- WIPO fieldOrganic fine chemistry
- WIPO sectorChemistry
Abstract
A process for removing iodine or soluble iodide impurities from a carboxylic acid or carboxylic acid anhydride, the carboxylic acid or carboxylic acid anhydride having been by a carbonylation process. The process includes: step (a) treating impure carboxylic acid or carboxylic acid anhydride containing iodine or soluble iodide impurities with an unsupported scavenger at a temperature of between 20.degree. and 250.degree. C. and step (b) thereafter separating the treated carboxylic acid or carboxylic acid anhydride from the scavenger. The scavenger is a silver salt in the absence of a trialkyl phosphine, a triaryl phosphine and a heterocyclic aromatic nitrogen compound. The preferred scavenger for acetic acid and acetic anhydride is silver acetate.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.