Bleed stream from electro refining step of copper smelter was processed to recover the metals as high value products such as copper and nickel powders or salts. The process consists of: partial de-copperisation of the bleed stream followed by crystallisation of a mixed salt of copper and nickel sulphate, leaching of the mixed salt, removal of iron, solvent extraction for separation of copper and nickel and winning the solution to produce metal powders. With the partially de-copperised bleed stream, the composite crystal was obtained by crystallisation which contained 8.4 -12.5 % Cu and 13.7-14.38 % Ni with 1-2ppm Fe as impurity. This mixed salt was leached with water and was treated for iron precipitation. The purified solution was subjected to solvent extraction using LIX 84 and Cyanex 272. A 20% LIX 84 in kerosene extracted 99.88% copper and 0.059% nickel at a pH of 2.5 and 5% Cyanex 272 in kerosene extracted 98.06% copper and 0.51% nickel at a pH of 4.85. LIX 84 was used for metal separation in the mixer-settler unit. The pure solutions of copper arid nickel sulphates obtained from stripping circuit were electrolysed to produce pure copper (99.9%) and nickel (99.8) powders; alternatively pure sulphate salts could also be crystallised.
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