湿法炼锌净化钴渣氧化沉淀法分离回收钴镍

Recovery of Cobalt and Nickel from Zinc Hydrometallurgy Purified Cobalt Residue by Oxidation Precipitation Method

针对湿法炼锌产出的多金属钴渣,采用一段硫酸浸出—二段高钴渣中和进行处理,所得含钴较高的浸出液依次采用过氧化氢氧化除铁、锌粉置换除镉、除镍试剂除镍、过硫酸钠选择性氧化除锰、过硫酸钠氧化沉钴处理,实现渣中镉、钴、镍、锌的分离回收。结果表明:在硫酸浓度150 g/L、温度80℃,浸出时间120 min的最佳酸浸条件下,浸出液中镉、镍均可除至0.1 mg/L以下,镉渣中镉含量高达57.61%,镍渣含镍10.74%,过硫酸钠沉钴率达到99.98%,钴渣含钴49.75%,沉钴后液返回湿法炼锌生产系统可回收金属锌,实现渣中金属资源的分离回收。

The multi metal cobalt residue produced by zinc hydrometallurgy is treated by primary sulfuric acid leaching and secondary high cobalt residue neutralization.The leachate with high cobalt content is successively treated by hydrogen peroxide oxidation to remove iron,zinc powder replacement to remove cadmium,nickel removal reagent to remove nickel,sodium persulfate selective oxidation to remove manganese,and sodium persulfate oxidation to deposit cobalt,to realize the separation and recovery of cadmium,cobalt,nickel and zinc in the residue.The results show that under the optimal acid leaching conditions of sulfuric acid concentration of 150 g/L,temperature of 80℃,leaching time of 120 min,cadmium and nickel in the leaching solution can be removed to less than 0.1 mg/L,the content of cadmium in the cadmium residue is as high as 57.61%,the content of nickel in the nickel residue is 10.74%,the rate of cobalt precipitation by sodium persulfate is 99.98%,and the content of cobalt in the cobalt residue is 49.75%.The liquid after cobalt precipitation can be returned to the zinc hydrometallurgy production system to recover metal zinc and realize the separation and recovery of metal resources in the residue.