Abstract: A hydrometallurgical process for the recovery of nickel and cobalt values from a sulfidic flotation concentrate. The process involves forming a slurry of the sulfidic flotation concentrate in an acid solution, and subjecting the slurried flotation concentrate to a chlorine leach at atmospheric pressure followed by an oxidative pressure leach. After liquid-solids separation and purification of the concentrate resulting in the removal of copper and cobalt, the nickel-containing solution is directly treated by electrowinning to recover nickel cathode therefrom.

Abstract: A hydrometallurgical process for the recovery of nickel and cobalt values from a sulfidic flotation concentrate. The process involves forming a slurry of the sulfidic flotation concentrate in an acid solution, and subjecting the slurried flotation concentrate to a chlorine leach at atmospheric pressure followed by an oxidative pressure leach. After liquid-solids separation and purification of the concentrate resulting in the removal of copper and cobalt, the nickel-containing solution is directly treated by electrowinning to recover nickel cathode therefrom.

Abstract: A hydrometallurgical process for the recovery of nickel and cobalt values from a sulfidic flotation concentrate. The process involves forming a slurry of the sulfidic flotation concentrate in an acid solution, and subjecting the slurried flotation concentrate to a chlorine leach at atmospheric pressure followed by an oxidative pressure leach. After liquid-solids separation and purification of the concentrate resulting in the removal of copper and cobalt, the nickel-containing solution is directly treated by electrowinning to recover nickel cathode therefrom.

Abstract: There is disclosed a process for separating and recovering nickel and copper values from a nickel-copper matte which may contain iron and arsenic. Finely divided nickel-copper matte undergoes one or more steps of sulphuric acid leaching at atmospheric pressure to produce a nickel sulphate solution and an iron and/or arsenic containing copper-rich sulphide residue. The copper-rich sulphide residue is repulped in sulphuric acid solution to selectively redissolve most of the iron and arsenic and the iron and arsenic containing solution is separated from the copper-rich residue. The iron and arsenic are largely precipitated from the leach solution in a pressure hydrolysis step and the iron and arsenic containing precipitate is separated and discarded. The iron and arsenic-depleted solution is recombined with the copper-rich sulphide residue from the acid repulp step and the resulting slurry is treated in a non-oxidizing pressure leach in which nickel arsenic and iron are extracted.