Method of preparing alkali metal fluoroalkylsulfonates of high purity
US4925975A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Apr 21, 1989 |
| Grant date | May 15, 1990 |
| Priority date | — |
| Expiry date | Apr 21, 2009 |
Classification
- Technology area (CPC C)Chemistry; Metallurgy
- CPC primaryC07C303/32
- WIPO fieldOrganic fine chemistry
- WIPO sectorChemistry
Abstract
In preparing a fluoroalkylsulfonate RfSO.sub.3 M, where Rf is a perfluoroalkyl gruop having not more than 6 carbon atoms and M is an alkali metal, by neutralization reaction between a fluoroalkylsulfonic acid RfSO.sub.3 H and an alkali metal carbonate or hydroxide, the reaction is carried out under acidic conditions such that at the end of the reaction pH of the reaction liquid is lower than 6, and preferably not higher than 3. By so maintaining the reaction liquid acidic, the obtained RfSO.sub.3 M becomes very low in the concentrations of anionic impurities such as free fluorine, free chlorine and carbonate radical and, besides becomes low in moisture absorbency.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.