Disclosed in the present invention is a method for preparing nickel sulfate from a nickel-iron-copper alloy. The method comprises: in a high-pressure oxygen environment, mixing a nickel-iron-copper alloy crushed material, aqueous ammonia, ammonium sulphate, and a corrosion assisting agent, leaching, then performing solid-liquid separation on the leached slurry, adding a precipitant into a filtrate, and performing ammonia distillation to obtain a nickel-containing leachate; then adding an extractant into the nickel-containing leachate to extract nickel so as to obtain a nickel-containing extraction organic phase; and then adding sulfuric acid into the nickel-containing extraction organic phase to perform back extraction of nickel so as to obtain a nickel sulfate solution. According to the present invention, the nickel-iron-copper alloy is separated by using different properties of nickel and iron, nickel is dissolved in a hexamine complex of nickel, iron cannot be dissolved and then continues to be remained in a solid, after the filtrate is collected, the precipitant is added and ammonia distillation is performed to remove copper, the aqueous ammonia is recycled, and the copper ions react with the precipitant to generate a copper sulfide precipitate, and thus, copper in the filtrate is removed, and the purity of nickel sulfate is further improved.

Disclosed in the present invention is a method for preparing nickel sulfate from a nickel-iron-copper alloy. The method comprises: in a high-pressure oxygen environment, mixing a nickel-iron-copper alloy crushed material, aqueous ammonia, ammonium sulphate, and a corrosion assisting agent, leaching, then performing solid-liquid separation on the leached slurry, adding a precipitant into a filtrate, and performing ammonia distillation to obtain a nickel-containing leachate; then adding an extractant into the nickel-containing leachate to extract nickel so as to obtain a nickel-containing extraction organic phase; and then adding sulfuric acid into the nickel-containing extraction organic phase to perform back extraction of nickel so as to obtain a nickel sulfate solution. According to the present invention, the nickel-iron-copper alloy is separated by using different properties of nickel and iron, nickel is dissolved in a hexamine complex of nickel, iron cannot be dissolved and then continues to be remained in a solid, after the filtrate is collected, the precipitant is added and ammonia distillation is performed to remove copper, the aqueous ammonia is recycled, and the copper ions react with the precipitant to generate a copper sulfide precipitate, and thus, copper in the filtrate is removed, and the purity of nickel sulfate is further improved.

This application pertains to methods of recovering metals from metal sulfides that involve contacting the metal sulfide with an acidic sulfate solution containing ferric sulfate and a reagent that has a thiocarbonyl functional group, wherein the concentration of reagent in the acidic sulfate solution is sufficient to increase the rate of metal ion extraction relative to an acidic sulfate solution that does not contain the reagent, to produce a pregnant solution containing the metal ions.

This application pertains to methods of recovering metals from metal sulfides that involve contacting the metal sulfide with an acidic sulfate solution containing ferric sulfate and a reagent that has a thiocarbonyl functional group, wherein the concentration of reagent in the acidic sulfate solution is sufficient to increase the rate of metal ion extraction relative to an acidic sulfate solution that does not contain the reagent, to produce a pregnant solution containing the metal ions.

A novel process for treating pickling acid residue and recovering sulfates and nickel therefrom has been developed. By lowering the pH of a magnesium compound slurry to 4-5.5 with sulfuric acid containing pickling acid residue in the presence of ammonium sulfate, both magnesium sulfate and nickel sulfate are solubilized. Magnesium sulfate and nickel sulfate solution is separated from the solids by filtration and an iron hydroxide and chromium hydroxide residue is obtained as a precipitate. Magnesium sulfate and nickel sulfate are then separated from the solution.

A novel process for treating pickling acid residue and recovering sulfates and nickel therefrom has been developed. By lowering the pH of a magnesium compound slurry to 4-5.5 with sulfuric acid containing pickling acid residue in the presence of ammonium sulfate, both magnesium sulfate and nickel sulfate are solubilized. Magnesium sulfate and nickel sulfate solution is separated from the solids by filtration and an iron hydroxide and chromium hydroxide residue is obtained as a precipitate. Magnesium sulfate and nickel sulfate are then separated from the solution.

A method for recovering an active metal of a lithium secondary battery according to an embodiment of the present application whereby a cathode active material mixture obtained from a used cathode of a lithium secondary battery is prepared, and the cathode active material mixture is reacted in a fluidized bed reactor to form a preliminary precursor mixture. A lithium precursor is recovered from the preliminary precursor mixture. Yield and selectivity of a lithium precursor can be improved using the fluidized bed reactor.

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.

Integrated recycling method and processes including recycling spent catalyst to produce one or more water-soluble metal salts and one or more water-insoluble tail byproducts, and recycling rechargeable batteries to produce one or more battery-grade metals and one or more pure metallic byproducts, wherein the water insoluble tail byproduct is a feedstock in recycling the rechargeable batteries, the impure metallic byproduct is a feedstock in recycling the spent catalyst, or both.