湿法富集铅冰铜中的贵金属

Hydrometallurgical Beneficiation of Precious Metals in Lead Copper Matte

针对铅冰铜的物相组成,提出了加压酸浸除铜—碳化转化铅—硝酸浸出铅的全湿法富集贵金属工艺,考察了浸出压力、温度、时间、硫酸浓度、液固体积质量比对铜浸出率的影响以及铜浸出渣碳化转化—硝酸浸出铅的条件。结果表明:在氧气压力1.2MPa、浸出温度120℃、浸出时间3h、硫酸质量分数20%、液固体积质量比4∶1、搅拌转速250r/min的最佳条件下,铜浸出率为97.21%;在碳化温度50℃、碳酸氢铵用量为理论量的1.2倍、碳化时间1.5h、液固体积质量比4∶1、硝酸用量为理论量的1.1倍的最佳条件下,铅转化率在96%以上,铅浸出率为99.8%;铅冰铜中的贵金属得到富集,富集比达到3.5倍。该工艺可用于从铅冰铜中富集贵金属。

Based on the compositions of lead copper matte, a hydrometallurgical process for beneficiating precious metals in lead copper matte was put forward which consists of pressure leaching copper-carbonation conversion lead-nitric acid leaching lead. The effects of pressure, temperature, leaching time, sulfuric acid concentration, the ratio between liquid volume and solid mass on leaching of copper,carbonation conversion of lead, nitric acid leaching of lead were examined. The results show that at the optimum leaching conditions of pressure of 1. 2 MPa, leaching temperature of 120 ℃, leaching time of 3 hours,sulfuric acid concentration of 20 %, the ratio of liquid volume and solid mass of 4 ： 1, stirring speed of 250 r/min, the leaching rate of copper is 97. 21%. Under carbonation temperature of 50 ℃, actual usage to theoretical usage of ammonium bicarbonate of 1. 2 times, carbonation time 1.5 hours,the ratio between liquid volume and solid mass of 4 ： 1, actual amount to theoretical amount of nitric acid of 1.1 times,convertion rate and leaching rate of lead from the above leaching residues is 97.21 ~ and 99.80/60 respectively. Realized beneficiation rate of precious metals in the lead copper matte is 3.5. The process can be used to enrich precious metals in lead copper matte.