Abstract:Cyanide tailings have the characteristics of large production, difficult recovery and reuse, high hazard, and high value of recovery. Different sources of cyanide tailings have different elemental states, so different processing technologies are required. The phase composition of roasted cyanide tailings was investigated, and it is found that the water-insoluble phase mainly consists complex slag particles formed by iron oxides, incompletely oxidized sulfides, and partial sulfides; the water-soluble phase is a sulfate salt containing about 7% sodium-calcium. The correlation between gold-iron dissolution was studied, and it is found that the porous structure of hematite in the tailings encapsulated gold. During the aqua regia leaching process, the gold-iron leaching rate has a similar trend. Therefore, a reduction-roasting cyanidation process was adopted. Under the conditions of 7% coke consumption, roasting temperature of 650 ℃, roasting time of 2 h, leaching slurry concentration of 25%, slurry pH value of 10.5, sodium cyanide concentration of 8‰, and leaching time of 24 h, the residue gold extraction rate is 76.43%.