Provided is a method of producing high-purity nickel sulfate by an impurity-element removal method for selectively removing Mg from a Ni-containing solution. The method comprises a production process of producing nickel sulfate from a Ni-containing acid solution, the acid solution being treated in order of steps (1) to (3): (1) carbonation step, adding a carbonating agent into the Ni-containing solution to make Ni contained in the Ni-containing solution into a precipitate of nickel carbonate or a mixture of nickel carbonate and nickel hydroxide, thereby forming a slurry after carbonation including the precipitate and a solution after carbonation; (2) solid-liquid separation step, separating the slurry after carbonation formed in the carbonation step into the precipitate and the solution after carbonation; and (3) neutralization step, adding a neutralizing agent into the solution after carbonation separated through the solid-liquid separation step to recover Ni contained in the solution after carbonation as a Ni-precipitate.

Provided is a method of producing high-purity nickel sulfate by an impurity-element removal method for selectively removing Mg from a Ni-containing solution. The method comprises a production process of producing nickel sulfate from a Ni-containing acid solution, the acid solution being treated in order of steps (1) to (3): (1) carbonation step, adding a carbonating agent into the Ni-containing solution to make Ni contained in the Ni-containing solution into a precipitate of nickel carbonate or a mixture of nickel carbonate and nickel hydroxide, thereby forming a slurry after carbonation including the precipitate and a solution after carbonation; (2) solid-liquid separation step, separating the slurry after carbonation formed in the carbonation step into the precipitate and the solution after carbonation; and (3) neutralization step, adding a neutralizing agent into the solution after carbonation separated through the solid-liquid separation step to recover Ni contained in the solution after carbonation as a Ni-precipitate.

Provided herein is a nickel recovering method, comprising: (A-i) a reduction heat treatment process for thermally treating a first raw material containing nickel and lithium; (B) a first leaching process for leaching the heat-treated product produced by the reduction heat treatment process; (A-ii) a roasting process for thermally treating a second raw material containing nickel and sulfur; (C) a second leaching process for leaching the first leaching residue produced by the first leaching process and calcine produced by the roasting process; (D) a neutralization process for neutralizing the second leachate produced by the second leaching process; and (E) a purification process for removing impurities contained in the neutralized solution produced by the neutralization process.

Provided herein is a nickel recovering method, comprising: (A-i) a reduction heat treatment process for thermally treating a first raw material containing nickel and lithium; (B) a first leaching process for leaching the heat-treated product produced by the reduction heat treatment process; (A-ii) a roasting process for thermally treating a second raw material containing nickel and sulfur; (C) a second leaching process for leaching the first leaching residue produced by the first leaching process and calcine produced by the roasting process; (D) a neutralization process for neutralizing the second leachate produced by the second leaching process; and (E) a purification process for removing impurities contained in the neutralized solution produced by the neutralization process.

Process to decrease silicon content of metal powder produced by hydrogen reduction from ammoniacal ammonium sulphate solutions containing metal ammine complexes, wherein metal (Me) is Ni, Co, or Cu. The process controls the precipitation of metal hydroxide, which is found to be an effective scavenger for silicon. Silicon is preferentially removed from metal diammine sulphate-containing solutions by precipitating with a small amount of a metal hydroxide, and then separating the silicon-bearing metal hydroxide precipitate from the solution. This solution, from which the silicon impurity has been removed with the metal hydroxide precipitate, can then be reduced in one or more densification cycles with a reducing gas to produce an elemental metal powder having a decreased silicon content. Alternatively, the solution is reduced to produce a low silicon metal powder seed material for the first of the one or more densification cycles.

Process to decrease silicon content of metal powder produced by hydrogen reduction from ammoniacal ammonium sulphate solutions containing metal ammine complexes, wherein metal (Me) is Ni, Co, or Cu. The process controls the precipitation of metal hydroxide, which is found to be an effective scavenger for silicon. Silicon is preferentially removed from metal diammine sulphate-containing solutions by precipitating with a small amount of a metal hydroxide, and then separating the silicon-bearing metal hydroxide precipitate from the solution. This solution, from which the silicon impurity has been removed with the metal hydroxide precipitate, can then be reduced in one or more densification cycles with a reducing gas to produce an elemental metal powder having a decreased silicon content. Alternatively, the solution is reduced to produce a low silicon metal powder seed material for the first of the one or more densification cycles.

The disclosure discloses a method for preparing a battery-grade nickel-cobalt-manganese sulfate solution from low nickel matte. The method includes the following steps: grinding low nickel matte, then adding the ground low nickel matte to concentrated sulfuric acid, and carrying out atmospheric pressure leaching to obtain a first slag phase and a first liquid phase; carrying out evaporation concentration-cooling crystallization on the first liquid phase to obtain ferrous sulfate crystals; adding concentrated sulfuric acid to the first slag phase, and carrying out oxygen pressure leaching to obtain a second slag phase and a second liquid phase; adjusting pH of the second liquid phase to 3-4 to generate a precipitate, and removing the precipitate by filtration to obtain a filtrate; carrying out adsorption treatment on the filtrate by adopting chelating resin; washing the adsorbed chelating resin with a first sulfuric acid solution to obtain a washing solution containing Mg and Mn, and then washing the chelating resin with a second sulfuric acid solution to obtain a nickel-cobalt sulfate solution; and mixing the nickel-cobalt sulfate solution with the washing solution containing Mg and Mn to obtain the nickel-cobalt-manganese sulfate solution. According to the method of the disclosure, the battery-grade nickel-cobalt sulfate solution is prepared from the low nickel matte as a raw material, so that the recovery rate of nickel and cobalt is increased, and the acid consumption is reduced.

The disclosure discloses a method for preparing a battery-grade nickel-cobalt-manganese sulfate solution from low nickel matte. The method includes the following steps: grinding low nickel matte, then adding the ground low nickel matte to concentrated sulfuric acid, and carrying out atmospheric pressure leaching to obtain a first slag phase and a first liquid phase; carrying out evaporation concentration-cooling crystallization on the first liquid phase to obtain ferrous sulfate crystals; adding concentrated sulfuric acid to the first slag phase, and carrying out oxygen pressure leaching to obtain a second slag phase and a second liquid phase; adjusting pH of the second liquid phase to 3-4 to generate a precipitate, and removing the precipitate by filtration to obtain a filtrate; carrying out adsorption treatment on the filtrate by adopting chelating resin; washing the adsorbed chelating resin with a first sulfuric acid solution to obtain a washing solution containing Mg and Mn, and then washing the chelating resin with a second sulfuric acid solution to obtain a nickel-cobalt sulfate solution; and mixing the nickel-cobalt sulfate solution with the washing solution containing Mg and Mn to obtain the nickel-cobalt-manganese sulfate solution. According to the method of the disclosure, the battery-grade nickel-cobalt sulfate solution is prepared from the low nickel matte as a raw material, so that the recovery rate of nickel and cobalt is increased, and the acid consumption is reduced.

The present invention provides a process for the preparation of a nickel sulphate solution in a column reactor, whereby metal particles containing nickel are reacted with an oxidative leach solution comprising sulphuric acid and hydrogen peroxide in water and whereby the acid in the oxidative leaching solution is substantially depleted.

The present invention provides a process for the preparation of a nickel sulphate solution in a column reactor, whereby metal particles containing nickel are reacted with an oxidative leach solution comprising sulphuric acid and hydrogen peroxide in water and whereby the acid in the oxidative leaching solution is substantially depleted.