Study of the Technology for Gold Recovery from Gravity-Flotation Concentrate from Ore Beneficiation with the use of Oxidizing Reagents

Gold-containing ore processing technology has been developed by using chemical, X-ray phase, mineralogical, X-ray fluorescence analyses. The results of experiments on the gold recovery from a concentrate with a particle size of 10 and 4 µm are presented, including options for direct cyanidation without preliminary oxygen oxidation, as well as with the use of preliminary oxidation of Trichloroisocyanuric acid (TCCA) and Sulfanol surfactant (SAS). It was found that the test sample contains 24.74 g/t Au; 11.66% S; 18.51% Fe. The content of sulfide minerals is 36.1%, the main sulfides are arsenopyrite (25.4%) and pyrite (10.7%). Microscopic examination of the combined gravity-flotation concentrate revealed ultrafine, fine and visible gold dust particles both in free form and in aggregations with waste rock. The particle size of Au in the product varies from 0.5 to 18.8 μm. 77.12% of gold is recovered from concentrate of 10 μm by direct cyanidation. “Sulfanol” was used to recover 83.71% of gold. Pre-treatment with TCCA yielded 85.61% of gold. Recovery of gold from the 4 μm concentrate was 75.38% for direct cyanidation, 78.79% for cyanidation with Sulfanol surfactant, 76.52% for cyanidation with TCCA.