Recovery of fluoride from waste solutions
US5413682A · kind A · utility
3Cited by
3References
5Claims
0Family size
Assignee
Inventors
Key dates
| Filing date | Mar 28, 1994 |
| Grant date | May 9, 1995 |
| Priority date | — |
| Expiry date | Mar 28, 2014 |
Classification
- Technology area (CPC C)Chemistry; Metallurgy
- CPC primaryC02F2201/46115
- WIPO fieldChemical engineering
- WIPO sectorChemistry
Abstract
Fluoride is recovered from an aqueous ammonium fluoride and ammonium hydroxide solution by electrolyzing the solution in an electrochemical cell having an ion-exchange membrane between a catholyte chamber and an anolyte chamber whereby hydrofluoric acid is formed and the concentration of ammonium hydroxide is enriched. Part of the hydrofluoric acid can be combined with the ammonium fluoride remaining after the ammonium hydroxide had been stripped from the treated solution to produce ammonium acid fluoride.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.