从湿法炼锌生产的锌置换渣中回收钴

RECOVERY OF COBALT FROM RESIDUE OF ZINC DISPLACEMENT

通过对湿法炼锌生产中锌置换渣的物料性质分析 ,发现回收钴所要分离的主要杂质是锌。控制 pH值3.2～ 3.8,反应时间 3h ,2段选择性浸出 ,锌钴的分离系数可达 195 .1。含Co溶液经过 2段沉淀除杂 ,D2EHPA(NH4+ )萃取 ,H2 SO4反萃取 ,反萃取水相结晶得到硫酸钴产品。

In the field of hydrometallurgical production of zinc,2 stages zinc displacement is used to remove cation impurities from its sulfate solution,by which cobalt may presents in the filter cake.In order to recover cobalt,minor cobalt has to be separated from major zinc metal and its compounds. Under the conditions of pH 3.2～3.8,3 h stirring time,and the filter cake exposed in air less than 5 days,the separating coefficient of Co/Zn is 195.1 through 2 stages leaching.After then,the leaching solution is processed by precipitation and solvent extraction for removing other impurities,from which 93.65% CoSO_4·7H_2O is obtained.