Provided is a method for producing lithium hydroxide, which can obtain lithium hydroxide from lithium sulfate with a relatively low cost. A method for producing lithium hydroxide from lithium sulfate includes: a hydroxylation step of allowing the lithium sulfate to react with barium hydroxide in a liquid to provide a lithium hydroxide solution; a barium removal step of removing barium ions in the lithium hydroxide solution using a cation exchange resin and/or a chelate resin; and a crystallization step of precipitating lithium hydroxide in the lithium hydroxide solution that has undergone the barium removal step.

Provided is a method for concentrating a valuable metal contained in a lithium ion secondary battery, for processing a lithium ion secondary battery containing at least one element selected from the group consisting of cobalt and nickel, or a positive electrode material of the lithium ion secondary battery, to concentrate a valuable metal containing either or both of cobalt and nickel. The method includes a thermal treatment step of thermally treating the lithium ion secondary battery or the positive electrode material thereof, to form a granular aggregate containing at least one valuable metal selected from the group consisting of cobalt and nickel.

The present invention is a method for treating an alloy, by which a solution that contains nickel and/or cobalt is obtained from an alloy that contains copper, zinc, and nickel and/or cobalt, said method comprising: a leaching process wherein a leachate is obtained by subjecting the alloy to a leaching treatment by means of an acid in the coexistence of a sulfurizing agent; a reduction process wherein the leachate is subjected to a reduction treatment with use of a reducing agent; and an ion exchanging process wherein a solution that contains nickel and/or cobalt is obtained by bringing a solution, which has been obtained in the reduction process, into contact with an amino phosphoric acid-based chelate resin, thereby having zinc adsorbed on the amino phosphoric acid-based chelate resin.

A method of making black mass from lithium containing batterie includes the steps of closing a chamber enclosing lithium-containing batteries and injecting nitrogen into the chamber to create an atmosphere sufficiently low in oxygen to prevent explosions and burning of the lithium-containing batteries. The lithium-containing batteries are shredded in the nitrogen atmosphere to produce shredded batteries. The shredded batteries are heated in the nitrogen atmosphere to a temperature sufficient to vaporize electrolyte and plastics from the batteries and produce pyrolyzed fragments. Lithium is present in a water-soluble nitrate form within the pyrolyzed fragments. The pyrolyzed fragments are classified to produce a black mass and a remaining metals fraction. The remaining metals fraction can be further classified to recover ferrous metals, light metals, and heavy metals.

Provided is a method for recovering valuable metals contained in waste batteries, wherein valuable metals can be efficiently recovered while suppressing a reduction in recovery rate. The method according to the present invention for recovering valuable metals from waste batteries comprises: a roasting step S1 for roasting a waste battery; a crushing step S2 for inserting an obtained roasted material into a crushing container, and crushing the roasted material using a chain mill; and a sieving step S3 for sieving an obtained crushed material and separating the crushed material into sieve upper material and sieve lower material. A chain mill equipment that is used in the crushing process is provided with: a rotating axial rod vertically erected with respect to a bottom surface of a crushing container; and a chain attached to a side surface of the rotating axial rod.

Provided is a method for recovering lithium, for recovering lithium from a lithium ion secondary battery, the method including: a thermal treatment step of thermally treating a lithium ion secondary battery having a residual voltage higher than or equal to 80% of a rated voltage, to obtain a thermally treated product; a pulverizing step of pulverizing the thermally treated product, to obtain a pulverized product; and a lithium recovering step of recovering lithium from the pulverized product.

A system for processing a waste lithium-ion battery includes: a first aqueous solution generator that includes a first elution tank storing water, and that immerses an active material taken out from the waste lithium-ion battery in the water in the first elution tank and subjects the active material to carbon dioxide bubbling in the first elution tank to generate an aqueous solution of pH 5.5 to 8.5, in which lithium contained in the active material is eluted; a first solid-liquid separator that removes a solid component from the aqueous solution generated by the first aqueous solution generator; a first crystallizer that causes lithium carbonate to be deposited from the aqueous solution, from which the solid component has been removed by the first solid-liquid separator; and a second solid-liquid separator that performs solid-liquid separation on slurry containing the lithium carbonate deposited in the first crystallizer to take out the lithium carbonate.

The purpose is to provide a method for recovering a valuable metal at low cost. The present invention is a method for recovering a valuable metal, the method comprising a step of preparing a burden material containing at least a valuable metal to obtain a raw material, a step of subjecting the raw material to an oxidation treatment and a reductive melting treatment to produce a reduced product containing an alloy and a slag, and a step of separating the slag from the reduced product to collect the alloy, in which the copper grade, which is a ratio of the mass of copper (Cu) to the total mass of nickel (Ni), cobalt (Co) and copper (Cu) contained in the alloy (i.e., a Cu/(Ni+Co+Cu) ratio), is adjusted to 0.250 or more.

A method for heat-treating battery waste containing lithium includes: allowing an atmospheric gas containing oxygen and at least one selected from the group consisting of nitrogen, carbon dioxide and water vapor to flow in a heat treatment furnace in which the battery waste is arranged, and heating the battery waste while adjusting an oxygen partial pressure in the furnace.

Provided is a method for delaminating a composite by immersing the composite into a delamination solution; wherein the composite comprises a substrate and a coating applied on one side or both sides of the substrate comprising a polymeric binder; and wherein the polymeric binder comprises a copolymer comprising a structural unit derived from an acid group-containing monomer. The use of weak acid-containing delamination solution allows for complete delamination of the composite in a highly efficient manner. Furthermore, the delamination method disclosed herein circumvents complex separation process, contamination and corrosion of substrate and enables an excellent materials recovery. An application of the method for delaminating an electrode for a battery is also disclosed.