Process for recovery of gold from refractory ores
US5071477A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | May 3, 1990 |
| Grant date | Dec 10, 1991 |
| Priority date | — |
| Expiry date | May 3, 2010 |
Classification
- Technology area (CPC C)Chemistry; Metallurgy
- CPC primaryC22B11/08
- WIPO fieldMaterials, metallurgy
- WIPO sectorChemistry
Abstract
The present invention is directed to an improvement in a process for the recovery of gold from refractory sulfidic auriferous ores which comprises oxidizing a slurry of ore with oxygen gas under pressure in the presence of sulfuric acid, neutralizing the oxidized slurry, cyanidizing the neutralized slurry to leach gold therefrom, and recovering gold from the resultant leachate. In accordance with the improved process, the oxidation of the ore slurry is carried out in a manner whereby, after a startup phase during which oxidation is initiated, the amount of sulfuric acid added to the ore slurry is sufficient to insure the oxidation of that portion of the sulfide sulfur in the ore which will allow recovery, by cyanide leaching, of at least about 80% of the gold in the ore. The oxidized slurry can be neutralized without a washing operation.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.