Sumitomo Metal Mining Company, Ltd.

Hitoshi Ishida

Satoshi Asano

Takayuki Nakai

Keiji Kudo

Yukie Kawakami

Masatoshi Takano

Kazunari Maeba

Masahiro Tanaka

Provided is a production method and a production apparatus that increase a throughput of nickel sulfate per equipment. A first dissolution step I of introducing a nickel briquette, sulfuric acid, and water to a leaching tank () and dissolving the nickel briquette to obtain a primary nickel sulfate solution, and a second dissolution step II of introducing the primary nickel sulfate solution and additionally introducing a nickel briquette to a leaching adjustment tank () and dissolving the additionally introduced nickel briquette with free sulfuric acid in the primary nickel sulfate solution to obtain a nickel sulfate solution are executed in this order. With the leaching adjustment tank () having a role as a concentration adjustment tank that increases a nickel concentration and decreases a free sulfuric acid concentration, and the leaching tank () supplied with the sulfuric acid and the water in addition to the nickel briquette, a continuous dissolution is achievable without increasing a retention time and without unnecessarily enlarging the equipment.

Production method and production apparatus for nickel sulfate solution

To provide a method for recovering lithium, that is capable of efficiently recovering lithium without containing impurities, such as phosphorus and fluorine, from a lithium-containing solution containing lithium hexafluorophosphate and separated from a lithium ion battery. In the present invention, alkali hydroxide is added to the lithium-containing solution and the solution is made to have pH 9 or more, a precipitate of a phosphate and a fluoride salt is formed, the formed precipitate is separated and removed, and then lithium is recovered from filtrate.

Method for recovering lithium

The object of the present invention is to provide a method for recovering a rare earth element, which is capable of efficiently recovering a rare earth element with high recovery rate without using any expensive chemicals, solvents or the like. In the present invention, a water-soluble salt other than sulfate ions is allowed to coexist with an aqueous solution that contains a rare earth element, and then an alkali metal sulfate is added to the aqueous solution, thereby producing a precipitate of a double sulfate of the rare earth element.

Method for recovering rare earth element

To provide a lithium recovery method which is capable of efficiently recovering lithium without containing impurities, such as phosphorus and fluorine. In the present invention, an alkali is added to a discharge liquid and/or a cleaning liquid containing lithium discharged in a process of recovering valuable metals from a lithium ion battery, an acidic solvent extractant is caused to be in contact with the discharge liquid and/or the cleaning liquid under a condition of pH 9 or less and a temperature of 0 to 25&#xb0; C. and lithium ions are extracted, and the acidic solvent extractant having extracted the lithium ions is caused to be in contact with an acid solution of pH 3 or less and the lithium ions are stripped.

Lithium recovery method

The present invention provides a valuable metal leaching method and a valuable metal collection method, in each of which valuable metals can be leached efficiently, the amount of a reducing agent used can be reduced, and cost reduction can be achieved. In the present invention, a positive electrode material is immersed in an acidic solution together with a metal having a lower reduction potential than a reduction potential of hydrogen, whereby valuable metals are leached out from a positive-electrode active substance.

Valuable metal leaching method, and valuable metal collection method employing the leaching method

The present invention aims at improving a recovery rate of a positive-pole active substance and preventing a recovery loss of valuable metals when a positive-pole active substance is separated from a lithium ion battery. In the present invention, a material resulting from battery dismantling obtained by dismantling a lithium ion battery is stirred using a surfactant solution, whereby a positive-pole active substance is separated from a positive-electrode substrate. Also, it is preferable that an alkaline solution is added to a positive-electrode material of a material resulting from battery dismantling, thereby dissolving a positive-electrode substrate to which a positive-pole active substance adheres to obtain a slurry containing the positive-pole active substance, and a surfactant solution is added to the slurry to disperse the positive-pole active substance in the slurry, whereby the positive-pole active substance is separated from the alkaline solution.

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Ehime, Japan

Hitoshi Ishida