Removal of Cu from the nickel electrolysis anolyte using nickel thiocarbonate

In this research, a novel reagent, nickel thiocarbonate (NiCS3), was synthesized to remove Cu from the nickel electrolysis anolyte. Through the experimental research, the effect of reagent amount of NiCS3, reaction temperature, pH value and reaction time on the copper removal was investigated. The experimental results showed that NiCS3 had high reaction activity, and Cu in the nickel electrolysis anolyte can be removed quickly. With the optimal reaction conditions of reagent amount of NiCS3 1.4-1.6 times of theoretical amount, reaction temperature of >= 60 degrees C, pH value of 4.0 and reaction time of 30 min, the Cu concentration was reduced to less than 3 mg/l in the nickel electrolysis anolyte and the mass ratio of Cu/Ni in the Cu-removal precipitates exceeded 15. The result can well satisfy the production requirement of qualified electrodeposited nickel. Therefore, NiCS3 can be used as the high-efficiency reagent to remove copper from the nickel electrolysis anolyte in the large-scale industrial production. (C) 2012 Elsevier B.V. All rights reserved.