Abstract: Processes for the recovery or purification of lithium species from various sources are described. Such sources include natural sources or deposits, such as in mining applications, and synthetic or non-natural sources, such as in the recycling of lithium species from batteries. In embodiments, the process comprises treating a Li2SO4-comprising aqueous solution with one or more barium salts to form a precipitate comprising barium sulfate (BaSO4). In embodiments, the processes may further comprise the preparation of a lithium sulfate-containing solution via treatment of the starting material or mixture with sulfuric acid. In embodiments, further treatments may be performed, for example prior to and/or subsequent to treatment with one or more barium salts, for example for initial or further sulfate removal, and/or removal of other metal species that may be present. The recovered lithium species be used directly, or converted into other forms, for use in a variety of applications.

Abstract: Methods are provided for processing a lithium-containing material (e.g., a mineral like spodumene) whereby a lithium sulfate solution derived from the material is reacted with a primary reagent (e.g., Na2CO3 or NaOH) to produce a mixed solution of primary lithium product (e.g., Li2CO3 or LiOH) and Na2SO4. In addition to primary lithium product, a separated Na2SO4 solution is produced and converted to a byproduct (e.g., CaSO4, NaNO3, NaOH, H2SO4) by reaction with a salt chemical (e.g., Ca(NO3)2) or alkali chemical (e.g., Ca(OH)2), or by electrolysis or electrodialysis. Byproducts are re-used to reduce reagent inputs. Residual lithium in an output solution is reacted with a secondary reagent (e.g., CO2 from flue gas, or H3PO4) to produce secondary lithium products (e.g., Li2CO3 or Li3PO4), which may be re-used to reduce reagent inputs and increase lithium recovery.

Abstract: Methods are provided for processing a lithium-containing material, such as spodumene, whereby a lithium sulfate solution derived from the material is reacted with sodium hydroxide to produce an intermediate solution comprising a first and second portion comprising lithium hydroxide and sodium sulfate. Lithium hydroxide and sodium sulfate are produced from the first portion. Lithium carbonate and sodium sulfate are produced from the second portion by reacting the intermediate solution with carbon dioxide. The intermediate solution may also be subjected to freezing thereby separating the lithium hydroxide from the sodium sulfate, and the separated lithium hydroxide may be reacted with carbon dioxide to produce a lithium product comprising lithium carbonate. Sodium sulfate from these processes may be reacted with an alkali chemical to produce a byproduct and a sodium hydroxide reaction fluid.