A method of selectively extracting lithium from a lithium sulfate aqueous solution, the method comprising: (i) mixing an aluminum-containing sorbent material into the lithium sulfate aqueous solution to form a precursor mixture, wherein the aluminum-containing sorbent material is an aluminum hydroxide, aluminum oxide, or combination thereof; and (ii) heating the precursor mixture to a temperature of 50-200° C. to result in selective formation of a solid lithium-aluminum complex and mother liquor; and wherein the method may further comprise: (iii) recovering isolated lithium salt from the solid lithium-aluminum complex by heating the solid lithium-aluminum complex in water or aqueous solution at a temperature of 50-100° C. to result in delithiation of the solid lithium-aluminum complex with transfer of the lithium salt from the solid lithium-aluminum complex to the water or aqueous solution, along with production of aluminum hydroxide solid.

This invention relates to treated geothermal brine compositions containing reduced concentrations of lithium, iron and silica compared to the untreated brines. Exemplary compositions contain concentration of lithium ranges from 0 to 200 mg/kg, concentration of silica ranges from 0 to 30 mg/kg, concentration of iron ranges from 0 to 300 mg/kg. Exemplary compositions also contain reduced concentrations of elements like arsenic, barium, and lead.

There are provided methods for preparing lithium carbonate. For example, such methods can comprise reacting an aqueous composition comprising lithium hydroxide with CO.sub.2 by sparging the CO.sub.2 the said composition, thereby obtaining a precipitate comprising the lithium carbonate. The methods can also comprise inserting at least a portion of the precipitate into a clarifier and obtaining a supernatant comprising lithium bicarbonate and a solid comprising the lithium carbonate, separating the solid from the supernatant; and heating the supernatant at a desired temperature so as to at least partially convert the lithium bicarbonate into lithium carbonate.

There are provided methods for preparing lithium carbonate. For example, such methods can comprise reacting an aqueous composition comprising lithium hydroxide with CO.sub.2 by sparging the CO.sub.2 the said composition, thereby obtaining a precipitate comprising the lithium carbonate. The methods can also comprise inserting at least a portion of the precipitate into a clarifier and obtaining a supernatant comprising lithium bicarbonate and a solid comprising the lithium carbonate, separating the solid from the supernatant; and heating the supernatant at a desired temperature so as to at least partially convert the lithium bicarbonate into lithium carbonate.

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.

Processes are provided for the selective recovery of lithium from brines using aqueous redox reactions, involving lithium extraction into a particulate ferric phosphate solid in the form of an iron (III) heterosite, in the presence of a reducing agent capable of reducing ionic lithium, at a controlled lithium extraction pH. Lithium elution involves exposing the loaded lithium ferrous phosphate solids, in the form of lithium iron (II) triphylite, to an oxidizing agent capable of mediating the oxidation of the sequestered atomic lithium. This is carried out at a controlled acidic lithium elution pH. Conditions in the lithium extraction and elution steps are provided so that a concentrated liquid lithium eluate is provided to subsequent steps of impurity removal and lithium carbonate precipitation.

Processes are provided for the selective recovery of lithium from brines using aqueous redox reactions, involving lithium extraction into a particulate ferric phosphate solid in the form of an iron (III) heterosite, in the presence of a reducing agent capable of reducing ionic lithium, at a controlled lithium extraction pH. Lithium elution involves exposing the loaded lithium ferrous phosphate solids, in the form of lithium iron (II) triphylite, to an oxidizing agent capable of mediating the oxidation of the sequestered atomic lithium. This is carried out at a controlled acidic lithium elution pH. Conditions in the lithium extraction and elution steps are provided so that a concentrated liquid lithium eluate is provided to subsequent steps of impurity removal and lithium carbonate precipitation.

The present disclosure concerns an aluminosilicate having a Blaine fineness of about 500 m.sup.2/kg to about 3000 m.sup.2/kg and/or a specific surface area of about 4 m.sup.2/g to about 20 m.sup.2/g, as well as the uses thereof. The present disclosure also comprises a dry cementing composition and a mortar or concrete composition, the compositions comprising said aluminosilicate. The present disclosure also comprises a process for the manufacture of aluminosilicate. The process comprises: roasting a spodumene concentrate in an acid medium; leaching the acidic roast spodumene concentrate so as to obtain a mixture comprising a solid comprising the aluminosilicate and a leachate; and separating the aluminosilicate from the leachate in an acid medium, wherein said aluminosilicate contains a calcium concentration of less than about 5%.

Lithium recycling from expended Li-Ion batteries occurs thought selective recovery of lithium charge materials from a recycling stream including transition metals used for the charge material. Li recovery includes dissolving the lithium based charge material in an organic acid having a resistance or lack of affinity to dissolution of transition metals, and distilling a leach solution formed from the dissolved charge material for generating a powder including lithium and trace impurities of the transition metals. Sintering of the generated powder forms lithium carbonate and carbonates of the trace impurities that eluded the selective leach, however, since the trace impurities are insoluble in water, the lithium carbonate is recoverable by water washing.