Abstract: The invention provides a method for recovering scandium from scandium-containing intermediate products, formed during hydrometallurgical processing of scandium-containing feed materials, including: (a) leaching of the scandium-containing intermediate products with a suitable acid at a controlled pH selected to maximize scandium extraction and minimize the co-extraction of impurities, (b) solid/liquid separation, to obtain a scandium-containing leach solution; (c) selective precipitation of the scandium at a controlled pH from the scandium-containing leach solution using a suitable base, (d) solid/liquid separation, to obtain an upgraded scandium concentrate and a barren solution for return to the hydrometallurgical process. A further upgraded scandium concentrate can be obtained by (e) alkaline leaching of the upgraded scandium concentrate for additional removal of impurities, and (f) solid/liquid separation to obtain a further upgraded scandium concentrate and impurities-containing base solution.

Abstract: The invention provides a method for recovering scandium from scandium-containing intermediate products, formed during hydrometallurgical processing of scandium-containing feed materials, including: (a) leaching of the scandium-containing intermediate products with a suitable acid at a controlled pH selected to maximize scandium extraction and minimize the co-extraction of impurities, (b) solid/liquid separation, to obtain a scandium-containing leach solution; (c) selective precipitation of the scandium at a controlled pH from the scandium-containing leach solution using a suitable base, (d) solid/liquid separation, to obtain an upgraded scandium concentrate and a barren solution for return to the hydrometallurgical process. A further upgraded scandium concentrate can be obtained by (e) alkaline leaching of the upgraded scandium concentrate for additional removal of impurities, and (f) solid/liquid separation to obtain a further upgraded scandium concentrate and impurities-containing base solution.

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.