在添加铜、镉、锑的条件下,对锌粉置换除钴深度净化硫酸锌溶液进行研究。考察初始铜离子浓度(ρ(Cu2+)0)、初始镉离子浓度(ρ(Cd2+)0)、锌粉用量、温度和搅拌转速等因素对净化除钴速率和效果的影响。试验结果表明:添加一定量的Cu2+不仅能提高除钴速率和效果,同时也能减少锌粉用量;同时添加Cu2+和Cd2+,除钴效果比单独添加Cu2+时更好。试验确定的最优除钴工艺条件为:ρ(Cu2+)015 mg/L,ρ(Cd2+)015 mg/L,酒石酸锑钾3 mg/L,锌粉2 g/L,温度85℃和搅拌转速300 r/min。
The cementation of cobalt by zinc dust in the presence of copper, cadmium and antimony additives was investigated experimentally for the purpose of deeply purifying zinc electrolyte. The effects of initial mass concentrations of Cu(II) ions (p(Cu2+)0), Cd(II) ions (p(Cd2+)o), dosage of zinc dust, temperature and stirring speed on the rate of cobalt removal and the purities of the zinc sulfate solution were examined. The results show that adding a certain amount of Cu(II) ions not only increases the cobalt removal rate together with the purities of zinc sulfate solution, but also saves the dosage of zinc dust used in the purification process. It is also validated that adding Cu(II) and Cd(II) ions at the same time behaves a better effect of cobalt removal than adding Cu(II) ions solely. The optimal conditions for cobalt removal are obtained as follows: p(Cu2+)0 15 mg/L, p(Cd2+)o 15 mg/L, antimony potassium tartrate 3 mg/L, zinc dust dosage 2 g/L, temperature 85 ℃ and stirring speed 300 r/min.