Abstract
The aqueous pressure oxidation of gold bearing arsenopyrite concentrates in alkaline solution was investigated as a function of O2 pressure and NaOH concentration. Dissolution of gold from the leach residue was accomplished by standard cyanidation. Gold extraction was found to be proportional to the degree of arsenopyrite oxidation. Alkaline pressure oxidation at l60°C, 2413 kPa O2 and 2 M NaOH resulted in about 98% sulfur oxidation and 86% arsenic dissolution. Cyanidation of the leach residue resulted in 82% Au extraction. This value for gold extraction is lower than what is typically achieved by acid pressure oxidation followed by cyanidation. A preliminary mineralogical study of the pressure oxidation leach residues was undertaken. The degree of gold recovery from the leach residues is believed to be linked to its association with oxidized products such as iron arsenate hydrate and iron oxide.
Original language | English (US) |
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Pages (from-to) | 61-74 |
Number of pages | 14 |
Journal | Mineral Processing and Extractive Metallurgy Review |
Volume | 15 |
Issue number | 1-4 |
DOIs | |
State | Published - Dec 1 1995 |
Externally published | Yes |
ASJC Scopus subject areas
- General Chemistry
- Geotechnical Engineering and Engineering Geology
- Mechanical Engineering
- Economic Geology