The recovery of metallic cadmium from the cadmium containing residue in a electrolytic zinc plant

Luong Manh Hung1, Tran Ngoc Vuong1
1 Institute for Technology of Radioactive and Rare Elements, Vietnam Atomic Energy Institute, 48 Lang-Ha str., Hanoi, Vietnam

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Abstract

This report presents a process for recovery and purification of metallic cadmium from a residue of the purification process for zinc sulphate solution in Thai Nguyen electrolytic zinc plant. The cadmium containing residue was digested by sulfuric acid of 140 g/l at a temperature of 700C for 4h, the obtained solution will be purified for removal of some impurities such as iron, copper, etc. The purified solution with concentration 50 g/l of Cd,  120 g/l of sulphuric acid and 0.1 g/l of gelatin as an additive will be subjected to an electrolysis process with current density of 50 A/m2 for recovery of metallic cadmium. The temperature of electrolyte is lower 400C. Overall recovery of cadmium is 90%,  purity of the obtained metalic cadmium  is up to 99.0%.

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References

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