Extraction of precious metals from ores thereof
US5320720A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Jan 5, 1993 |
| Grant date | Jun 14, 1994 |
| Priority date | — |
| Expiry date | Jan 5, 2013 |
Classification
- Technology area (CPC C)Chemistry; Metallurgy
- CPC primaryC22B11/08
- WIPO fieldMaterials, metallurgy
- WIPO sectorChemistry
Abstract
Increased efficiency of extraction of silver and gold from ore materials thereof containing active carbonaceous material is obtained by conducting the extraction in two stages. In a first stage a portion of the silver and of the gold when present is extracted in a cyanide leach solution. The leached solids residue is contacted with activated carbon so that the silver and the gold when present are adsorbed on the activated carbon at elevated temperature (most preferably at about 35.degree. C. to about 100.degree. C.). In a modification, a slurry of the ore material is treated with cyanide and the precious metal adsorbed directly from the cyanided slurry with activated carbon at elevated temperature up to about 70.degree. C.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.