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.

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.

An ion-exchange apparatus includes a raw-water tank 1, a treatment section, an ion exchanger and a hydrophilic layer. The raw-water section contains a liquid to be treated with impurity ions. The treatment tank 2 contains a treatment material with exchange ions exchangeable with the impurity ions. The ion exchanger 3 enables the passage of the impurity ions from the raw-water tank 1 to the treatment tank 2 and the passage of the exchange ions from the treatment tank 2 to the raw-water tank 1. The hydrophilic layer M, with a water contact angle of 30° or less, is disposed on at least a surface of the ion exchanger adjacent to the treatment tank 2.

An inexpensive ion-exchange apparatus with an increased ion-exchange capacity has a raw-water tank (1), a treatment tank (2) and an ion exchanger (3). The raw-water tank (1) contains a to be treated liquid. The liquid contains impurity ions. The treatment tank (2) contains a treatment material that contains exchange ions exchangeable with the impurity ions. The ion exchanger (3) enables passage of the impurity ions from the raw-water tank (1) to the treatment tank (2) and the passage of the exchange ions from the treatment tank (2) to the raw-water tank (1). The treatment material in the treatment tank (2) has a higher molarity than the to be treated liquid in the raw-water tank 1.

An apparatus (100) for producing an acidic aqueous solution includes: an electrodialyzer (110) that has a monovalent ion perm-selective ion-exchange membrane and separates wastewater containing chloride ions and alkali metal ions into electrodialysis concentrated water and electrodialysis diluted water by an electrodialysis treatment; an electrolyzer (120) includes an anode that that electrolyzes the electrodialysis concentrated water to produce an acidic aqueous solution; and a first circulator (13) that circulates at least some of the acidic aqueous solution to the wastewater supplied to the electrodialyzer (110), and that adjusts a pH of the wastewater supplied to the electrodialyzer to 3 to 9.

Electrodialysis cell systems for water deionization is provided. Also provided are methods for using the electrodialysis cell systems. The cells use the forward and reverse reactions of a redox mediator and the combined operations of a deionization cell and an ion-accumulation cell to enable sustainable deionization with a significantly decreased operating voltage, relative to conventional deionization cells. The cells have applications in seawater desalination, water purification, and wastewater treatment.

A treatment of demineralization effluents, particularly recycling effluents, a method for demineralizing whey and treating the effluents, and a facility for implementation thereof. The treatment of whey demineralization effluents includes: i) supplying a whey demineralization effluent, ii) treating by reverse osmosis effluent recovered in i) to obtain a reverse osmosis permeate and retentate, iii) neutralizing the retentate pH, iv) treating the neutralized retentate by nanofiltration to obtain a permeate including monovalent ions and a retentate including divalent ions and residual organic materials, v) treating the permeate in iv) by electrodialysis with bipolar membrane to obtain acidic solution(s) and basic solution(s). Thus, it is possible to treat effluents, limit their environmental impact, generate solutions for the whey demineralization process, reduce the cost of whey demineralization because some process water from electrodialysis comes from treatment of the generated effluents, and reduce the total amount of effluent sent to the wastewater treatment plant.

The present invention provides a method of deionization of a liquid including passing feedwater to be deionized through a deionization fuel cell system, which includes a deionization fuel cell (DFC), containing, inter alia, a cation exchange membrane and an anion exchange membrane and discharging the DFC to produce electricity and deionized liquid, wherein the method does not include a step of charging the fuel cell prior to or following the discharge step. Further provided are deionization fuel cell systems comprising a DFC comprising two or more membranes.

The present disclosure provides devices and methods of using same for cleansing a solution (e.g., a salt or used dialysis solution) of urea via electrooxidation, and more specifically to cleansing a renal therapy solution/dialysis solution of urea via electrooxidation so that the renal therapy solution/dialysis solution can be used or reused for treatment of a patient. In an embodiment, a device for the removal of urea from a fluid having urea to produce a cleansed fluid includes a urea decomposition unit and an electrodialysis unit.