Optimization and mechanism of gold-bearing sulfide flotation

In order to overcome the difficulty of extracting gold from gold-bearing sulfide ore by cyanide process, flotation was adopted based on mineralogical analysis. Mineralogy shows that gold particles are of superfine structure and mainly enclosed by sulfide ores. Primary gold-bearing sulfide ore is fine-grained pyrite and arsenopyrite. The paper describes the effects of ratios and dosage of activators and collectors on the recovery and grade of gold concentrate. A proper flotation flowsheet was then proposed based on experimental condition and closed-circuit test. The gold concentrate with the gold grade of 25.14 g center dot ton(-1) and the recovery of 86.94 % is obtained after one rougher, three cleaners, and four scavengers from fine grinding flotation process. Furthermore, the mechanisms of combined activators and combined collectors were studied by thermodynamic calculation, and structure-activity relationship of flotation reagent was also explained.