Process for recovering lithium values
AssigneesLivium Ltd., Australian Nuclear Science and Technology Organisation
InventorsAndrew Napier, Christopher Griffith
Life of this patent
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Abstract
A process for recovering lithium phosphate and lithium sulfate from a lithium-bearing solution, such as a brine or pregnant process liquor is described. The process includes adding phosphate to the lithium-bearing solution to precipitate lithium phosphate and then separating the resulting lithium phosphate precipitate from the solution. The separated lithium phosphate precipitate is then digested in sulphuric acid to produce a digestion mixture from which a lithium sulfate precipitate is separated. An alkali metal hydroxide is added to the separated solution to produce an alkali metal phosphate solution and this is recycled for use as phosphate in the first step of the process.
Claims20
A process for recovering lithium phosphate from a lithium-bearing solution comprising:
- a) adding phosphate to the lithium-bearing solution to produce a lithium phosphate precipitate;
- b) separating the lithium phosphate precipitate from a solution produced in step a);
- b1) dissolving the separated lithium phosphate precipitate in a solution comprising phosphoric acid at a pH of about pH 4 to about pH 6 to re-precipitate the lithium phosphate;
- b2) separating the re-precipitated lithium phosphate from the phosphoric acid solution.
Dependencies are inferred from the claim text.