卡林型金精矿氧压渣中铁矾碱性分解及环保提金试验研究

Experimental study on the jarosite decomposition of the oxygen-pressed residue from Carlin-type gold concentrates in the alkaline system and the environmentally friendly gold extraction

卡林型金精矿酸性加压氧化预处理所得氧压渣中存在铁矾二次包裹金现象,采用环保型提金剂浸金,金浸出率约为81%。为了进一步提高金浸出率,考察了碱性体系不同工艺参数条件下氧压渣中铁矾分解规律及对金浸出率的影响,并确定了最优条件。结果表明:在pH值11.0~12.0、液固比4、搅拌速度400 r/min、时间3 h、温度90℃条件下,可实现对铁矾的高效分解。以优化条件下所得铁矾分解渣为原料,采用环保型提金剂作为浸金剂,金浸出率可达89.6%,表明碱性体系铁矾分解工序可有效打开铁矾对金的包裹,有效提高金浸出率。

Secondary jarosite encasement of gold was observed in the oxygen-pressed residue obtained from acidic pressure oxidation pretreatment of Carlin-type gold concentrates.An environmentally friendly gold extraction agent was used to extract gold,with a gold leaching rate of approximately 81%.To further improve the gold leaching rate,the decomposition law of jarosite in the oxygen-pressed residue under different process parameters in an alkaline system was investigated,as well as its effect on the gold leaching rate,and the optimal conditions were determined.The results showed that efficient decomposition of jarosite can be achieved under the conditions of pH 11.0-12.0,liquid-solid ratio of 4,stirring speed of 400 r/min,time of 3 h,and temperature of 90℃.The gold extraction rate of up to 89.6%was achieved using the environmentally friendly gold extraction agent with the optimized jarosite decomposition residue as the raw material,indicating that the jarosite decomposition process in an alkaline system can effectively relieve the encased gold and effectively improve the gold leaching rate.