Disposal of copper electrofining solutions

The paper presents studies of the processing of spent copper electrolyte from the processing of non-ferrous metal scrap at a copper smelter in Kazakhstan. For the processing of the spent electrolyte, a stage-by-stage neutralization was carried out using zinc sublimates and potash. As a result of the first stage of neutralization with zinc sublimations to pH 4.7, a precipitate with a content of PbO 44.69 %; PO2 16.36 % was obtained. After processing the sediment with an alkaline solution, carbonization and melting at a temperature of 900 oC, metallic lead and tin-containing slag with a content of SnO2 of 16.36 % were obtained. As a result of the second stage of neutralization with potash to pH 7.1, a precipitate was obtained-with a CuO content of 76.45 %. After the third stage of neutralization with potash to pH 9.5, a precipitate with a content of NiO 27.63 % and ZnO 55.75 % was obtained. After treatment of the precipitate with a solution containing 100 g / dm3 KOH, a zinc-containing solution with a ZnO content of 225.0 g/dm3 and a precipitate were obtained, after calcination of which nickel oxide with a NiO content of 89.14 % was obtained.