A method of separating and recovering a cobalt salt and a nickel salt includes a separation step of separating, by using a nanofiltration membrane, a cobalt salt and a nickel salt from a rare metal-containing aqueous solution containing at least both the cobalt salt and the nickel salt as rare metals, in which the nanofiltration membrane has a glucose permeability of 3 times or more a sucrose permeability, the sucrose permeability of 10% or less, and an isopropyl alcohol permeability of 50% or more when a 1,000 mg/L glucose aqueous solution, a 1,000 mg/L sucrose aqueous solution, and a 1,000 mg/L isopropyl alcohol aqueous solution, each having a pH of 6.5 and a temperature of 25 C., individually permeate through the nanofiltration membrane at an operating pressure of 0.5 MPa.

A method of separating and recovering a cobalt salt and a nickel salt includes a separation step of separating, by using a nanofiltration membrane, a cobalt salt and a nickel salt from a rare metal-containing aqueous solution containing at least both the cobalt salt and the nickel salt as rare metals, in which the nanofiltration membrane has a glucose permeability of 3 times or more a sucrose permeability, the sucrose permeability of 10% or less, and an isopropyl alcohol permeability of 50% or more when a 1,000 mg/L glucose aqueous solution, a 1,000 mg/L sucrose aqueous solution, and a 1,000 mg/L isopropyl alcohol aqueous solution, each having a pH of 6.5 and a temperature of 25 C., individually permeate through the nanofiltration membrane at an operating pressure of 0.5 MPa.

A preparation method for a high nickel ternary precursor capable of preferential growth of crystal planes by adjusting and controlling the addition amount of seed crystals. The method comprises the following steps: 1) feeding a ternary metal solution into a reaction kettle containing a first base liquid for reaction, and when the particle size reaches 1.5 to 3.0 m, stopping the feeding, so as to obtain a seed crystal slurry; 2) simultaneously adding the ternary metal solution, a liquid alkali solution, and an ammonia solution in cocurrent flow into a growth kettle containing a second base solution for reaction, when the particle size reaches 6 to 8 m, adding the seed crystal slurry into the reaction system, and controlling the particle size to be 9.0 to 11.0 m by adjusting the feed rate of the seed crystal, so as to obtain the target object. In the preparation method, by adding seed crystals continuously, the crystal plane parameters of 001 peak in the prepared ternary precursor material is lower than the crystal plane parameters of 101 peak, facilitating the embedding of Li ions, and effectively improving the performance of a battery prepared by using the material.

A preparation method for a high nickel ternary precursor capable of preferential growth of crystal planes by adjusting and controlling the addition amount of seed crystals. The method comprises the following steps: 1) feeding a ternary metal solution into a reaction kettle containing a first base liquid for reaction, and when the particle size reaches 1.5 to 3.0 m, stopping the feeding, so as to obtain a seed crystal slurry; 2) simultaneously adding the ternary metal solution, a liquid alkali solution, and an ammonia solution in cocurrent flow into a growth kettle containing a second base solution for reaction, when the particle size reaches 6 to 8 m, adding the seed crystal slurry into the reaction system, and controlling the particle size to be 9.0 to 11.0 m by adjusting the feed rate of the seed crystal, so as to obtain the target object. In the preparation method, by adding seed crystals continuously, the crystal plane parameters of 001 peak in the prepared ternary precursor material is lower than the crystal plane parameters of 101 peak, facilitating the embedding of Li ions, and effectively improving the performance of a battery prepared by using the material.

The invention provides a process for generating a metal sulphide comprising nickel and/or cobalt, comprising the steps of: i. forming an aqueous metal sulphate solution by reacting sulphuric acid with a raw material feed comprising nickel and/or cobalt in water; ii. crystallizing said metal sulphate from said aqueous metal sulphate solution to form a crystallized metal sulphate in a mother liquor, the mother liquor comprising an uncrystallized metal sulphate; iii. separating said crystallized metal sulphate from said mother liquor; iv. reacting at least a portion of said uncrystallized metal sulphate with hydrogen sulphide in an acidic aqueous medium, thereby obtaining a slurry consisting of a solid phase comprising a metal sulphide precipitate and an aqueous phase comprising one or more impurities and sulphuric acid; and v. separating said solid phase and said aqueous phase.

A method for producing nickel sulfate according to exemplary embodiments may prepare a raw material containing nickel. A first leachate may be produced by selectively leaching nickel from the raw material containing nickel using an oxidant. A second leachate may be produced by separating a residual metal from the first leachate. Thereafter, nickel sulfate may be obtained from the second leachate. Accordingly, unnecessary byproducts may be reduced by omitting a separate nickel extraction step.

The present disclosure discloses a wet process for recovering valuable metals from a lithium battery. In the method, a waste lithium battery powder is subjected to selective leaching under the condition that a hydrogen sulfide gas is introduced through pressurization, such that Mn.sup.2+, Li.sup.+, and Al.sup.3+ metal ions enter a first-stage leaching liquor and nickel, cobalt, copper, and iron exist in a first-stage leaching residue in the form of a sulfide; then a pH of the first-stage leaching liquor is adjusted to remove aluminum and manganese, which achieves extremely thorough metal separation and leads to relatively pure products; a first-stage leaching residue is subjected to leaching in an acid liquor under a negative pressure, such that the sulfides of nickel, cobalt, iron, and copper are dissolved in a second-stage leaching liquor, and a hydrogen sulfide gas produced can be recycled in the first-stage leaching procedure through pressurization.

The present disclosure discloses a wet process for recovering valuable metals from a lithium battery. In the method, a waste lithium battery powder is subjected to selective leaching under the condition that a hydrogen sulfide gas is introduced through pressurization, such that Mn.sup.2+, Li.sup.+, and Al.sup.3+ metal ions enter a first-stage leaching liquor and nickel, cobalt, copper, and iron exist in a first-stage leaching residue in the form of a sulfide; then a pH of the first-stage leaching liquor is adjusted to remove aluminum and manganese, which achieves extremely thorough metal separation and leads to relatively pure products; a first-stage leaching residue is subjected to leaching in an acid liquor under a negative pressure, such that the sulfides of nickel, cobalt, iron, and copper are dissolved in a second-stage leaching liquor, and a hydrogen sulfide gas produced can be recycled in the first-stage leaching procedure through pressurization.

In a method for recovering an active metal of a lithium secondary battery, a sulfuric acid solution is added to a lithium metal composite oxide so as to prepare a sulfated active material solution. A transition metal is extracted from the sulfated active material solution. A lithium precursor is recovered by adding a lithium extracting agent to the solution remaining after the transition metal has been extracted from the sulfated active material solution. In the method, the amount of impurities is reduced, and sulfuric acid and the neutralizing agent can be recycled so that a high-yield lithium precursor recovery is enabled.

A process and method for producing a crystallized metal sulfate. The crystallized metal sulfate may be battery-grade. The method may comprise receiving a metal ion-containing stream and crystalizing a metal sulfate from the stream. The process may comprise receiving a stream from a metal processing plant, and crystalizing a metal sulfate from the stream. The process may be a metal electrowinning process comprising crystalizing a metal ion-containing stream to form a crystallized metal sulfate in a mother liquor. The process or method may comprise returning the mother liquor upstream or to the metal electrowinning process.