The present invention provides a process for preparing a high-purity nickel sulphate solution, comprising the steps of: i. providing an aqueous feed solution comprising nickel. cobalt, calcium and magnesium: ii. extracting cobalt, calcium, and partly magnesium from said aqueous feed solution using a first solvent comprising a first alkylphosphorus-based acidic extractant, thereby obtaining an aqueous raffinate comprising nickel and magnesium: iii. extracting magnesium from said aqueous raffinate solution comprising nickel and magnesium using a second solvent comprising a second alkylphosphorus-based acidic extractant, thereby obtaining a high-purity aqueous nickel sulphate solution comprising nickel and magnesium: iv. stripping the first loaded solvent comprising cobalt, calcium and magnesium with an aqueous solution comprising a mineral acid.

The present invention provides a process for preparing a high-purity nickel sulphate solution, comprising the steps of: i. providing an aqueous feed solution comprising nickel. cobalt, calcium and magnesium: ii. extracting cobalt, calcium, and partly magnesium from said aqueous feed solution using a first solvent comprising a first alkylphosphorus-based acidic extractant, thereby obtaining an aqueous raffinate comprising nickel and magnesium: iii. extracting magnesium from said aqueous raffinate solution comprising nickel and magnesium using a second solvent comprising a second alkylphosphorus-based acidic extractant, thereby obtaining a high-purity aqueous nickel sulphate solution comprising nickel and magnesium: iv. stripping the first loaded solvent comprising cobalt, calcium and magnesium with an aqueous solution comprising a mineral acid.

A process for generating a metal sulfate that involves crystallizing a metal sulfate from an aqueous solution to form a crystallized metal sulfate in a mother liquor with uncrystallized metal sulfate remaining in the mother liquor; separating the crystallized metal sulfate from the mother liquor; basifying a portion of the mother liquor to convert the uncrystallized metal sulfate to a basic metal salt; and using the basic metal salt upstream of crystallizing the metal sulfate. So crystallized, the generated metal sulfate may be battery-grade or electroplating-grade.

A process for generating a metal sulfate that involves crystallizing a metal sulfate from an aqueous solution to form a crystallized metal sulfate in a mother liquor with uncrystallized metal sulfate remaining in the mother liquor; separating the crystallized metal sulfate from the mother liquor; basifying a portion of the mother liquor to convert the uncrystallized metal sulfate to a basic metal salt; and using the basic metal salt upstream of crystallizing the metal sulfate. So crystallized, the generated metal sulfate may be battery-grade or electroplating-grade.

It is provided a process for extracting nickel sulfate from mining ores, such as serpentine, comprising the steps of conducting a magnetic separation of the mining ores producing a magnetic fraction and a non magnetic fraction; leaching the non magnetic fraction with HCl producing a slurry comprising metals chloride; filtrating the slurry producing a metals chloride liquor; purifying the metals chloride liquor producing a magnesium chloride solution; separating an iron-nickel cake from the magnesium chloride solution; leaching the cake together with the magnetic fraction producing a metallic sulfate solution; extracting nickel and cobalt from the metallic sulfate solution by a ion exchange resin extraction and stripping producing an inorganic stripped phase; submitting the inorganic stripped phase to a liquid-liquid extraction producing a nickel concentrated phase; and evaporating and drying the nickel concentrated phase to recuperate nickel sulfate.

It is provided a process for extracting nickel sulfate from mining ores, such as serpentine, comprising the steps of conducting a magnetic separation of the mining ores producing a magnetic fraction and a non magnetic fraction; leaching the non magnetic fraction with HCl producing a slurry comprising metals chloride; filtrating the slurry producing a metals chloride liquor; purifying the metals chloride liquor producing a magnesium chloride solution; separating an iron-nickel cake from the magnesium chloride solution; leaching the cake together with the magnetic fraction producing a metallic sulfate solution; extracting nickel and cobalt from the metallic sulfate solution by a ion exchange resin extraction and stripping producing an inorganic stripped phase; submitting the inorganic stripped phase to a liquid-liquid extraction producing a nickel concentrated phase; and evaporating and drying the nickel concentrated phase to recuperate nickel sulfate.

The present invention provides a method for directly preparing nickel sulfate from low nickel matte, a nickel sulfate and an application thereof, the method comprising the following steps: a) pre-treating a low nickel matte to obtain ferronickel powder; b) mixing the ferronickel powder with a sulfuric acid solution, stirring, dissolving, and then evaporating, to obtain a supersaturated sulfate solution; c) cooling the supersaturated sulfate solution to 5 C.-0 C., and performing suction filtration to obtain an insoluble solid; d) washing the insoluble solid with water, and removing impurities from the filtrate to obtain a nickel hydroxide precipitate; impurity removal comprising successively removing iron, and removing calcium and magnesium; e) washing the nickel hydroxide precipitate with water, acid-dissolving and evaporating to obtain nickel sulfate. The present invention increases the amount of nickel recovered, the purity of nickel sulfate being 18.10%-19.24% nickel, and the recovery rate being 94.8%-97.1%.

The present invention provides a method for directly preparing nickel sulfate from low nickel matte, a nickel sulfate and an application thereof, the method comprising the following steps: a) pre-treating a low nickel matte to obtain ferronickel powder; b) mixing the ferronickel powder with a sulfuric acid solution, stirring, dissolving, and then evaporating, to obtain a supersaturated sulfate solution; c) cooling the supersaturated sulfate solution to 5 C.-0 C., and performing suction filtration to obtain an insoluble solid; d) washing the insoluble solid with water, and removing impurities from the filtrate to obtain a nickel hydroxide precipitate; impurity removal comprising successively removing iron, and removing calcium and magnesium; e) washing the nickel hydroxide precipitate with water, acid-dissolving and evaporating to obtain nickel sulfate. The present invention increases the amount of nickel recovered, the purity of nickel sulfate being 18.10%-19.24% nickel, and the recovery rate being 94.8%-97.1%.

A process recovers metals from a black mass. The process includes the following steps in the following order: step (a) providing the black mass, which comprises Li; step (b) adding water to the black mass and creating a suspension of the black mass in the water; step (c) dosing ozone as an oxidant to the suspension while stirring the suspension; and step (d) filtering and separating a filtrate containing LiOH dissolved in water from a Li depleted residue of the black mass. In step (c), the suspension is stirred with a shear rate greater than 11000 s.sup.1 within the suspension.

A process recovers metals from a black mass. The process includes the following steps in the following order: step (a) providing the black mass, which comprises Li; step (b) adding water to the black mass and creating a suspension of the black mass in the water; step (c) dosing ozone as an oxidant to the suspension while stirring the suspension; and step (d) filtering and separating a filtrate containing LiOH dissolved in water from a Li depleted residue of the black mass. In step (c), the suspension is stirred with a shear rate greater than 11000 s.sup.1 within the suspension.