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 invention is directed to an electrochemical device for at least partially removing or reducing a target ionic species from an aqueous solution using faradic immobilization, the electrochemical device including at least one first electrode and at least one second electrode with different void fraction and surface area properties, due to differences in void fraction (also referred to as void ratio) of the at least one first and the at least one second electrode, water flows through an electrode with a high porosity, while the aqueous solution does not flow through an electrode with a low porosity. The asymmetry of the electrodes provides a desired voltage distribution across the device, which equates to a different voltage at each electrode, to control the speciation of the target ionic species at the anode and the cathode.

An ion-exchange apparatus has a raw-water tank 1, a treatment tank 2, an ion exchanger 3 and a voltage applying device E. The raw-water tank 1 contains a to be treated liquid that has 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 voltage-applying device E applies a voltage to the ion exchanger 3.

A method of pumping an aqueous fluid through an electroosmotic membrane situated between a cathode and an anode includes oxidizing water to O.sub.2 at the anode and reducing O.sub.2 at the cathode. A potential difference E between the cathode and the anode is 1.4 V or less.

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 recovery device including an ion selective permeable membrane with an ion conductive layer containing a lithium ion conductor formed of an inorganic substance, and a support layer is formed of a porous body wherein the ion selective permeable membrane has a configuration (I). In configuration (I) the ion conductive layer is provided in contact with one principal surface side of a support layer, and an electrode is provided in contact with another principal surface side opposite to the one principal surface side on which the ion conductive layer is provided.

A system comprises an electrodialysis apparatus, which includes first and second reservoirs, wherein a salt concentration in the first reservoir reduces below a threshold concentration and salt concentration in the second reservoir increases during an operation mode. A first electrode comprises a first solution of a first redox-active electrolyte material, and a second electrode comprises a second solution of a second redox-active electrolyte material. In a first reversible redox reaction between the first electrode and first electrolyte material at least one ion is accepted from the first reservoir, and in a second reversible redox reaction between the second electrode and second electrolyte material at least one ion is driven into the second reservoir. A first type of membrane is disposed between the first and second reservoirs, and a second type of membrane, different from the first type, is disposed between the respective electrodes and reservoirs.

A water conditioning system of an electrodialysis reversal (EDR) water purifier includes a first source water inlet, a second source water inlet, an EDR film stack, a first conductive probe, a second conductive probe, a third conductive probe, a fourth conductive probe, a variable speed pump, a one-way valve, a clean water outlet, a waste water outlet, an electrode A, an electrode B, and a control system module. With the four conductive probes detecting conductivity of water flowing through four ports on two sides of the EDR film stack and by sending detected data to the control system module, the control system module adjusts voltages of the electrode A and electrode B accordingly to instantly increase or decrease removal efficiency of the EDR film stack. Thus, the conductivity of the discharged clean water and the quality of the clean water can be stabilized.

A flow-electrode cartridge unit and a submerged flow-electrode capacitive deionization device using the same are proposed. The flow-electrode cartridge unit includes a pair of porous current collector plates arranged to face each other in a spaced apart state from each other in a first direction, a pair of ion separation membranes positioned on respective outer surfaces of the porous current collector plates in the first direction, a channel frame for wrapping around the pair of porous current collector plates and the pair of ion separation membranes to expose each of the ion separation membranes in the first direction, thereby forming a flow electrode channel between the pair of porous current collector plates, a pair of communication holes formed in the channel frame and communicating the flow electrode channel to an outside, and an electrode terminal formed in the channel frame and electrically connected to the porous current collector plates.

Systems and methods for removing a contaminant from a liquid are generally described. The liquid (e.g., water) containing the contaminant may be flowed across a semipermeable membrane (e.g., via forward osmosis) that is not permeable to the contaminant in order to remove the contaminant from the liquid. A concentration gradient across the semipermeable membrane may be provided and maintained by electrolysis of the liquid and can drive forward osmosis of the liquid through the semipermeable membrane.