Recovery of gold from solution by reduction-precipitation with stabilized alkali metal borohydride
US5223023A · kind A · utility
9Cited by
3References
24Claims
0Family size
Assignee
Inventors
Key dates
| Filing date | Jan 30, 1991 |
| Grant date | Jun 29, 1993 |
| Priority date | — |
| Expiry date | Jan 30, 2011 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY02P10/20
- WIPO fieldMaterials, metallurgy
- WIPO sectorChemistry
Abstract
A process is disclosed for the direct recovery of gold from thiourea, thiocyanate or thiosulfate solutions or acidified thiourea leach liquor. The process comprises reduction precipitation of the gold from solution by the addition of stabilized alkali metal borohydride, preferably sodium or potassium borohydride, at ambient temperature and pressure. The resulting gold precipitate is generally of high purity and is readily separated by filtration. The barren solution is in a condition such that it can be recycled to the upstream process.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.