Electrochemical Pretreatment for Improved Leaching Rate of Refractory gold Ore with Large Cyanide Consumption

In this paper, the combined treatment of sodium peroxide addition and electro-oxidation for the pretreatment of refractory gold concentrate improved gold extraction. The conventional gold extraction rate was 17% with 40 kg/t of sodium cyanide without pretreatment, and the refractory gold concentrate with little cyanide concentration at 2h cyanide leaching time. Pretreatment and cyanide leaching were carried out at normal temperature and atmospheric pressure in alkaline media, in a single leaching bath, and a simple method without conventional separation operation. After pretreatment, the gold extraction increased from 17% to 88%.