An electrodialysis desalination device includes a first electrode including a first-stage side; a second electrode including a first-stage side; and a first stage between the first-stage side of the first electrode and the first-stage side of the second electrode. The first stage includes at least one first-stage cell pair positioned between the first-stage side of the first electrode and the first-stage side of the second electrode, and each cell pair includes a pair of first-stage selectively permeable ion-exchange membranes with alternating selectivity that define first-stage channels on opposite sides of each first-stage membrane for respective flows of a first-stage diluate stream and a first-stage concentrate stream. A single pump is configured to pump the diluate streams and the concentrate streams through the first stage.

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.

The present disclosure relates to a method for extracting lithium from a lithium-containing material. For example, the method can comprise leaching a roasted lithium-containing material under conditions suitable to obtain an aqueous composition comprising a lithium compound such as lithium sulfate and/or lithium bisulfate. The aqueous composition comprising lithium sulfate and/or lithium bisulfate can optionally be used, for example, in a method for preparing lithium hydroxide comprising an electromembrane process. The roasted lithium-containing material can be prepared, for example by a method which uses an aqueous composition comprising optionally lithium sulfate and/or lithium bisulfate which can be obtained from a method for preparing lithium hydroxide comprising an electromembrane process such as a two-compartment monopolar or bipolar electrolysis process.

The present disclosure relates to a method for extracting lithium from a lithium-containing material. For example, the method can comprise leaching a roasted lithium-containing material under conditions suitable to obtain an aqueous composition comprising a lithium compound such as lithium sulfate and/or lithium bisulfate. The aqueous composition comprising lithium sulfate and/or lithium bisulfate can optionally be used, for example, in a method for preparing lithium hydroxide comprising an electromembrane process. The roasted lithium-containing material can be prepared, for example by a method which uses an aqueous composition comprising optionally lithium sulfate and/or lithium bisulfate which can be obtained from a method for preparing lithium hydroxide comprising an electromembrane process such as a two-compartment monopolar or bipolar electrolysis process.

The present invention relates to a method for the production of drinking water. In addition, the present invention also relates to the use of minerals extracted from a feed water stream by using a combination of a Donnan dialysis unit and a membrane unit as a source of minerals for the production of drinking water originating from said feed water stream.

The present invention relates to a method for the production of drinking water. In addition, the present invention also relates to the use of minerals extracted from a feed water stream by using a combination of a Donnan dialysis unit and a membrane unit as a source of minerals for the production of drinking water originating from said feed water stream.

An anion exchange membrane is made by mixing 2 trifluoroMethyl Ketone [nominal] (1.12 g, 4.53 mmol), 1 Biphenyl (0.70 g, 4.53 mmol), methylene chloride (3.0 mL), trifluoromethanesulfonic acid (TFSA) (3.0 mL) to produce a pre-polymer. The pre-polymer is then functionalized to produce an anion exchange polymer. The pre-polymer may be functionalized with trimethylamine in solution with water. The pre-polymer may be imbibed into a porous scaffold material, such as expanded polytetrafluoroethylene to produce a composite anion exchange membrane.

An anion exchange membrane is made by mixing 2 trifluoroMethyl Ketone [nominal] (1.12 g, 4.53 mmol), 1 Biphenyl (0.70 g, 4.53 mmol), methylene chloride (3.0 mL), trifluoromethanesulfonic acid (TFSA) (3.0 mL) to produce a pre-polymer. The pre-polymer is then functionalized to produce an anion exchange polymer. The pre-polymer may be functionalized with trimethylamine in solution with water. The pre-polymer may be imbibed into a porous scaffold material, such as expanded polytetrafluoroethylene to produce a composite anion exchange membrane.

A method for separation and enrichment of lithium includes the following steps: pretreatment: diluting and filtering salina aged brine to obtain pretreated brine; separation: separating the pretreated brine via a nanofiltration separation system to obtain nanofiltration permeate and nanofiltration concentrate; first concentration: carrying out first concentration on the nanofiltration permeate via a reverse osmosis system to obtain reverse osmosis concentrate and reverse osmosis permeate; second concentration: carrying out second concentration on the reverse osmosis concentrate via an electrodialysis system to obtain electrodialysis concentrate and electrodialysis permeate, and the electrodialysis concentrate is solution enriching lithium ions. The present application couples several different membrane separation technologies by utilizing the advantages of different membrane separation technologies, thereby achieving the purposes of improving the separation efficiency of magnesium and lithium and improving the enrichment efficiency of lithium.

Disclosed is a process for enriching silicate content in drinking water that includes separating raw water via reverse osmosis into a permeate comprising demineralised raw water and a retentate comprising mineral enriched raw water. The permeate is mixed with a water glass solution comprising sodium silicate and/or potassium silicate. An ion exchange process is used to reduce the concentration of sodium and/or potassium ions in at least part of the mixture. At least part of the retentate is supplied to the mixture after reducing the concentration of sodium and/or potassium ions to provide a silicate-enriched drinking water. Also disclosed is an apparatus for producing a drinking water enriched with silicate. The apparatus includes a reverse osmosis unit, a mixing unit, an ion exchanger, and a feed unit for feeding at least part of the retentate to the mixture after reducing the concentration of sodium and/or potassium ions.