A method of producing lithium phosphate from a lithium source includes the step of (a) concentrating the lithium to produce a lithium concentrate, with an ion exchange sorbent, and (b) reacting the lithium concentrate with phosphate anions to produce lithium phosphate. The lithium phosphate may then be converted to lithium hydroxide or lithium 5 carbonate by reaction with calcium hydroxide or by electrolysis.

Embodiments relate to methods for generating selected materials from a natural brine, where the natural brine is sea water, saline water, fresh water, synthetic solutions, or industrial liquid wastes. A natural brine comprising at least a portion of a selected material is heated. CO.sub.2 is added and mixes with the natural brine forming a mixture such that the CO.sub.2/P is a first predetermined value. The mixture is held so that impurities in the natural brine precipitate as solids leaving a second brine substantially comprising the selected material. The second brine is heated. CO.sub.2 gas is injected into the second brine, mixing so that the CO.sub.2/P is a second predetermined value. The mixture is held so that the selected material precipitates out and are removed.

Embodiments relate to methods for generating selected materials from a natural brine, where the natural brine is sea water, saline water, fresh water, synthetic solutions, or industrial liquid wastes. A natural brine comprising at least a portion of a selected material is heated. CO.sub.2 is added and mixes with the natural brine forming a mixture such that the CO.sub.2/P is a first predetermined value. The mixture is held so that impurities in the natural brine precipitate as solids leaving a second brine substantially comprising the selected material. The second brine is heated. CO.sub.2 gas is injected into the second brine, mixing so that the CO.sub.2/P is a second predetermined value. The mixture is held so that the selected material precipitates out and are removed.

Systems and methods use ion exchange to extract lithium from a lithium-containing feed solution such as a salar brine. Lithium ions are loaded into an ion exchange resin and then eluted while recharging the resin. Sodium hydroxide or sodium bicarbonate may be used to recharge the resin but are not directly mixed with the lithium-containing feed solution. An eluate stream is produced containing lithium hydroxide or lithium bicarbonate. Lithium hydroxide can be precipitated as lithium hydroxide or in a hydrate form. Lithium bicarbonate may be converted to lithium carbonate. The system and method optionally includes processing an eluate stream to recover one or more compounds for re-use in regenerating the resin bed.

In this disclosure, a process of recycling acid, base and the salt reagents required in the Li recovery process is introduced. A membrane electrolysis cell which incorporates an oxygen depolarized cathode is implemented to generate the required chemicals onsite. The system can utilize a portion of the salar brine or other lithium-containing brine or solid waste to generate hydrochloric or sulfuric acid, sodium hydroxide and carbonate salts. Simultaneous generation of acid and base allows for taking advantage of both chemicals during the conventional Li recovery from brines and mineral rocks. The desalinated water can also be used for the washing steps on the recovery process or returned into the evaporation ponds. The method also can be used for the direct conversion of lithium salts to the high value LiOH product. The method does not produce any solid effluent which makes it easy-to-adopt for use in existing industrial Li recovery plants.

In this disclosure, a process of recycling acid, base and the salt reagents required in the Li recovery process is introduced. A membrane electrolysis cell which incorporates an oxygen depolarized cathode is implemented to generate the required chemicals onsite. The system can utilize a portion of the salar brine or other lithium-containing brine or solid waste to generate hydrochloric or sulfuric acid, sodium hydroxide and carbonate salts. Simultaneous generation of acid and base allows for taking advantage of both chemicals during the conventional Li recovery from brines and mineral rocks. The desalinated water can also be used for the washing steps on the recovery process or returned into the evaporation ponds. The method also can be used for the direct conversion of lithium salts to the high value LiOH product. The method does not produce any solid effluent which makes it easy-to-adopt for use in existing industrial Li recovery plants.

A hybrid electro-pressure driven method for the recovery, purification, and concentration of lithium salts is described. A fractionating electrodialysis stack equipped with selective ion exchange membranes is s used to separate a lithium containing brine into a monovalent enriched fraction and a divalent enriched fraction. The monovalent enriched fraction is further processed to remove remaining impurities by use of pressure driven nanofiltration. An optional concentrating electrodialysis device may further concentrate the monovalent enriched fraction in lithium content. The method may be combined with a subsequent solvent extraction and electrolysis step to produce lithium hydroxide, a Li+ selective sorbent step for producing purified lithium chloride, or a Li+ selective sorbent and precipitative step to produce lithium carbonate.

A hybrid electro-pressure driven method for the recovery, purification, and concentration of lithium salts is described. A fractionating electrodialysis stack equipped with selective ion exchange membranes is s used to separate a lithium containing brine into a monovalent enriched fraction and a divalent enriched fraction. The monovalent enriched fraction is further processed to remove remaining impurities by use of pressure driven nanofiltration. An optional concentrating electrodialysis device may further concentrate the monovalent enriched fraction in lithium content. The method may be combined with a subsequent solvent extraction and electrolysis step to produce lithium hydroxide, a Li+ selective sorbent step for producing purified lithium chloride, or a Li+ selective sorbent and precipitative step to produce lithium carbonate.

In a method for recovering an active metal of a lithium secondary battery according to an embodiment, a waste cathode active material mixture is prepared from a waste cathode of a lithium secondary battery. A preliminary precursor mixture is formed by reacting the waste cathode active material mixture with a reactive gas in a fluidized bed reactor. The preliminary precursor mixture is cooled by spraying different first and second refrigerants to the preliminary precursor mixture. A lithium precursor is recovered from the cooled preliminary precursor mixture.

A method for recovering lithium is provided. The method includes the following steps. A lithium-containing solution is provided. A manganese oxide adsorbent is immersed in the lithium-containing solution, and a reducing agent is added to carry out an adsorption reaction, and the manganese oxide adsorbent is immersed in a solution containing an oxidizing agent to carry out a desorption reaction.