Method for recovering nitric acid and purifying silver nitrate electrolyte
US8282903B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Jun 23, 2008 |
| Grant date | Oct 9, 2012 |
| Priority date | — |
| Expiry date | Jun 23, 2028 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY02P10/20
- WIPO fieldMaterials, metallurgy
- WIPO sectorChemistry
Abstract
A processes for the regeneration of a silver nitrate and nitric acid based electrolyte as used in certain silver refining processes is based on the hydrolytic removal of undesired metal-based compounds such as water insoluble hydrolysable base metal cations and water insoluble hydrolysable base metal nitrates from which the soluble silver nitrate and nitric acid based electrolyte may be separated. Water is added slowly to a dewatered electrolyte melt held at a predetermined, elevated, temperature while allowing nitric acid thereby formed to evolve and be separated from the melt while the water insoluble base metal salts are formed. The melt is then diluted with water to dilute the silver nitrate contained therein and the insoluble base metal salts are separated from the mixture by filtration.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.