Precious metal recovery from solution
US7972413B2 · kind B2 · utility
8Cited by
19References
37Claims
0Family size
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Key dates
| Filing date | Apr 5, 2007 |
| Grant date | Jul 5, 2011 |
| Priority date | — |
| Expiry date | Sep 6, 2027 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY02P10/20
- WIPO fieldMaterials, metallurgy
- WIPO sectorChemistry
Abstract
A method for recovering precious metals such as gold and silver from aqueous solution as solid is described The method includes mixing an aqueous solution (e.g, thiosulfate or thiocyanate lixiviant) containing precious metals with ferrous ions in the presence of an effective amount of hydroxide ions. The precious metal ions are reduced and co-precipitate with iron hydroxides and/or hydrated iron oxides The co-precipitate is collected and purified. De-oxygenation of the reaction solution is optional. The recover/method is fast, complete and clean.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.