A process for recovering alkali from power boiler ash is provided. The power boiler ash is first contacted with Na.sub.2CO.sub.3 to produce a mixture containing settling and non-settling solid particles. A fraction of the settling particles is then separated from the mixture to produce a first clarified alkaline solution. The first clarified alkaline solution contains species such as NaOH and KOH depending upon the power boiler ash characteristics. The non-settling solid particles may optionally be further separated from the first clarified alkaline solution to obtain a second clarified alkaline solution. This process is also applicable for the extraction of alkali from other oxide/hydroxide containing materials.

A method for preparing battery grade and high purity grade lithium hydroxide and lithium carbonate from high-impurity lithium sources includes steps for preparation of a refined lithium salt solution, preparation of battery grade lithium hydroxide, preparation of high purity grade lithium hydroxide, preparation of high purity grade lithium carbonate and preparation of battery grade lithium carbonate. The system to carry out the preparation includes a refined lithium salt solution preparation subsystem, a battery grade lithium hydroxide preparation subsystem, a high purity grade lithium hydroxide preparation subsystem, a high purity grade lithium carbonate preparation subsystem and a battery grade lithium carbonate preparation subsystem arranged in turn according to production sequence. A combination of physical and chemical treatment methods are used to treat the high-impurity lithium sources having variations in lithium contents, impurity categories, and impurity contents.

A method for preparing battery grade and high purity grade lithium hydroxide and lithium carbonate from high-impurity lithium sources includes steps for preparation of a refined lithium salt solution, preparation of battery grade lithium hydroxide, preparation of high purity grade lithium hydroxide, preparation of high purity grade lithium carbonate and preparation of battery grade lithium carbonate. The system to carry out the preparation includes a refined lithium salt solution preparation subsystem, a battery grade lithium hydroxide preparation subsystem, a high purity grade lithium hydroxide preparation subsystem, a high purity grade lithium carbonate preparation subsystem and a battery grade lithium carbonate preparation subsystem arranged in turn according to production sequence. A combination of physical and chemical treatment methods are used to treat the high-impurity lithium sources having variations in lithium contents, impurity categories, and impurity contents.

A method for preparing battery grade and high purity grade lithium hydroxide and lithium carbonate from high-impurity lithium sources includes steps for preparation of a refined lithium salt solution, preparation of battery grade lithium hydroxide, preparation of high purity grade lithium hydroxide, preparation of high purity grade lithium carbonate and preparation of battery grade lithium carbonate. The system to carry out the preparation includes a refined lithium salt solution preparation subsystem, a battery grade lithium hydroxide preparation subsystem, a high purity grade lithium hydroxide preparation subsystem, a high purity grade lithium carbonate preparation subsystem and a battery grade lithium carbonate preparation subsystem arranged in turn according to production sequence. A combination of physical and chemical treatment methods are used to treat the high-impurity lithium sources having variations in lithium contents, impurity categories, and impurity contents.

The invention relates to a method of using an aqueous solution discharged from an electrochemical apparatus for converting lithium salt dissolved in water to lithium hydroxide and the acid corresponding to the lithium salt, to produce lithium hydroxide monohydrate with simultaneous conversion of this solution to the catholyte required to enter the electrochemical apparatus. The conversion of the aqueous solution into the catholyte is preferably accomplished by a balance discharge of lithium hydroxide monohydrate as a wet product, cooling of the catholyte to remove to balance the amount of heat introduced into the catholyte with the electrochemical process, and balance refreshing of the catholyte with lithium salt in a stirred vessel. In an additional washing step, the balance of the water also reacted during the electrochemical conversion of the lithium salts used is balanced. The lithium hydroxide monohydrate product thus produced is also an object of the invention.

The invention relates to a method of using an aqueous solution discharged from an electrochemical apparatus for converting lithium salt dissolved in water to lithium hydroxide and the acid corresponding to the lithium salt, to produce lithium hydroxide monohydrate with simultaneous conversion of this solution to the catholyte required to enter the electrochemical apparatus. The conversion of the aqueous solution into the catholyte is preferably accomplished by a balance discharge of lithium hydroxide monohydrate as a wet product, cooling of the catholyte to remove to balance the amount of heat introduced into the catholyte with the electrochemical process, and balance refreshing of the catholyte with lithium salt in a stirred vessel. In an additional washing step, the balance of the water also reacted during the electrochemical conversion of the lithium salts used is balanced. The lithium hydroxide monohydrate product thus produced is also an object of the invention.

The present invention is related to the production and concentration of lithium and potassium from natural sources, in particular from clays from salt flats.

The present invention is related to the production and concentration of lithium and potassium from natural sources, in particular from clays from salt flats.

Provided is a method for efficiently recovering metals from lithium ion battery waste while reducing the use of sodium hydroxide as a pH adjuster. A method for recovering metals from lithium ion battery waste includes wet processing of leaching metals containing lithium from lithium ion battery waste with an acid, and extracting the metals from the metal-containing solution in which the metals are dissolved, in which the lithium extracted in the wet processing is used as a pH adjuster used in the wet processing.

Provided is a method for efficiently recovering metals from lithium ion battery waste while reducing the use of sodium hydroxide as a pH adjuster. A method for recovering metals from lithium ion battery waste includes wet processing of leaching metals containing lithium from lithium ion battery waste with an acid, and extracting the metals from the metal-containing solution in which the metals are dissolved, in which the lithium extracted in the wet processing is used as a pH adjuster used in the wet processing.