| Aiming at the low leaching rate of arsenopyrite and pyrite-coated gold in a high-sulfur and high-arsenic gold mine in Myanmar, an alkaline leaching pretreatment process were developed to treat the gold mine. The effects of grinding time, solid-liquid ratio, pretreatment pH, catalyst ZNT dosage, pretreatment time, oxidant dosage and other factors on the gold leaching rate were investigated. The results showed that sulfur and arsenic encapsulating gold were effectiviely removed under the following conditions: adjusting pH=13 using NaOH , the grinding fineness -38 μm content accounted for 90%, adding 10 kg/t of catalyst ZNT and 40 kg/t of oxidant H2O2, pretreating with 1:6 of solid-liquid ratio for 12 h. After pretreatment, The pre-treated ore samples were leached for 24 hours under the conditions of 20 kg/t of gold leaching agent (1# Jinhu gold extracting agent) and slurry pH=13, and the gold leaching rate increased by nearly 30 percentage points. |
