镉离子对硫酸锌溶液除钴的影响及机理探索

Effect and Mechanism of Cadmium Ion on Cobalt Removal in Zinc Sulphate Solution

采用电子探针分析硫酸锌溶液净化渣,试图证实从硫酸锌溶液中除钴的机理。实验结果表明,Cd2+对除钴是很有益的,所以,在除钴之前把Cd2+完全除去是不完全正确的,应该把Cd2+作为除钴的一种添加剂。镉可以起到阻止碱式硫酸锌或氢氧化锌吸附在锌粉表面的作用。欲加速钴的置换和提高置换效率,必须形成锌-钴合金或锌-镉合金。锌-钴合金和锌-镉合金的共同形成比单独锌-钴合金的效果要好。锌-铜合金的形成,可能对提高除钴置换效率没有帮助。

The residues after cementation were analyzed by electron probe micro-analysis (EPMA) to research mechanism of cobalt removal. The results show a small amount of cadmium is beneficial in terms of the final cobalt concentration. It is an important consideration in purification circuits that removal cadmium completely prior to cobalt cementation, because cadmium can inhibit basic zinc sulphate to adsorb on the surface of zinc dust. To enhance cobalt, the Zn-Co or Zn-Cd alloys must form. The Zn-Co and the Zn-Cd alloys were found to enhance cobalt removal, whereas Zn-Cu and Cu-Cd alloys had an advarse effect on cobalt removal.