Abstract:Copper is difficult to separate from nickel electrolyte due to low concentration of copper (0.53 g/L) with high concentration of nickel (75 g/L). Manganese sulfide (MnS) was used to deeply remove copper from the electrolyte. Experimental results show that the concentration of copper (ρ(Cu)) decreases from 530 to 3 mg/L and the mass ratio of copper to nickel (R_Cu/Ni) in the residue reaches above 15 when the MnS dosage is 1.4 times the theoretical valueD_t,MnS (D_t,MnS=0.74 g) and the pH value of electrolyte is 4-5 with reaction time more than 60 min at temperatures above 60 °C. The concentration of newly generated Mn²⁺(ρ(Mn)) in the solution is also reduced to 3 mg/L by the oxidation reaction. The values ofρ(Cu), ρ(Mn)and R_Cu/Ni meet the requirements of copper removal from the electrolyte. It is shown that MnS can be considered a highly effectivedecoppering reagent.

Key words: MnS; decoppering reagent; copper removal; manganese removal; nickel anodic electrolyte