An electrodeionization device having an improved boron rejection capability compared with high-performance electrodeionization devices proposed in the related art is provided. An electrodeionization device comprising a cathode; an anode; and a plurality of cation-exchange membranes and a plurality of anion-exchange membranes, the plurality of cation-exchange membranes and the plurality of anion-exchange membranes being arranged between the cathode and the anode so as to form concentrating compartments and desalting compartments, the concentrating compartments and desalting compartments being arranged alternately, the desalting compartments being filled with an ion-exchange resin, wherein the ion-exchange resin has an average particle size of 100 to 300 ?m. Preferably, the ion-exchange resin has a uniformity coefficient of 1.1 or less.

A water treatment apparatus for removing dissolved oxygen contained in water to be treated includes: an anode; a cathode; and a dissolved oxygen removal chamber which is located between the anode and the cathode and filled with an ion exchanger. At least a portion of the ion exchanger filled in the dissolved oxygen removal chamber is an ion exchanger on which a metal catalyst is supported. The ion exchanger on which the metal catalyst is supported is filled in a single bed configuration in at least a portion of the dissolved oxygen removal chamber. A DC current is applied between the anode and the cathode.

A process for preparing an ion-exchange membrane having a textured surface profile comprising the steps (i) and (ii): (i) applying a radiation-curable composition to a membrane in a patternwise manner; and (ii) irradiating and thereby curing the radiation-curable composition present on the membrane; wherein the radiation-curable composition comprises: a) 10 to 65 wt % of curable ionic compound(s) comprising one ethylenically unsaturated group; b) 3 to 60 wt % of crosslinking agent(s) comprising at least two ethylenically unsaturated groups and having a number average molecular weight below 800; c) 0 to 70 wt % of inert solvent(s); d) 0 to 10 wt % of free-radical initiator(s); and e) 0.5 to 25 wt % of thickening agent(s).

An ion-permeable membrane is substantially free of holes and has excellent ion permeability, heat resistance, strength, and flexibility. A battery electrolyte membrane uses the ion-permeable membrane, and can form an electrode composite body. The polymer-ion-permeable membrane has an average radius of free volume of 0.32-0.50 nm.

A desalination battery cell includes a first compartment separated by an anion exchange membrane from a second compartment, each of the first and second compartments containing a saline water solution having a concentration of dissolved salts c.sub.1 and first and second intercalation host electrodes, respectively, in fluid communication with the solution, a voltage source supplying electric current to the first and second intercalation host electrodes to release cations into the solution, and a controller programmed to adjust an amount of the electric current being supplied to change direction of anions in the solution passing through the anion exchange membrane between the compartments such that the first and second compartments alternately collect and disperse salt from the solution and release desalinated water solution having a concentration c.sub.2 of dissolved salts and a brine solution having a concentration c.sub.3 of dissolved salts such that c.sub.3>C.sub.1>C.sub.2.

Systems and methods for electrochemical separation are provided. An electrochemical separation device may include at least one cell pair wound around an electrode to from a bundle having a racetrack configuration.

An ion processing device includes, on the side of an anion exchange layer of a bipolar membrane which is formed by stacking an anion exchange layer and a cation exchange layer, an anion-side channel which is filled with an anion exchanger, and an anion removal channel provided via an anion exchange membrane, and also includes an anode for moving anions from the anion-side channel to the anion removal channel through the anion exchange membrane. Further, a cation-side channel which is filled with a cation exchanger and a cation removal channel provided via a cation exchange membrane are included on the side of the cation exchange layer of the bipolar membrane as well as a cathode for moving cations from the cation-side channel to the cation removal channel through the cation exchange membrane.

A bipolar membrane electrodialysis method and system are described for purifying an organic acid from an aqueous solution containing the salt of the organic acid. The system includes a bipolar membrane electrodialysis stack that includes at least one three-compartment bipolar membrane electrodialysis cell and at least one two-compartment bipolar membrane electrodialysis cell. The method includes recirculating the solution of organic acid produced from the three-compartment bipolar membrane electrodialysis cell and two-compartment bipolar membrane electrodialysis cell. Cation or anion exchange resins may be included in the spacers of acid compartment to increase the conductivity of acid compartments, thereby increasing current density of the bipolar electrodialysis stack and decreasing power consumption.

Systems and methods for electrochemical separation are provided. An electrochemical separation device may include at least one cell pair wound around an electrode to from a bundle having a racetrack configuration.

The present disclosure is directed to ion-exchange systems and devices that can monitor key parameters related to the performance of the ion-exchange device. Specifically, the ion-exchange systems and devices disclosed herein can provide real time voltage drop across groups of membrane pairs using diagnostic spacer borders between the pairs. In addition, the ion-exchange systems and devices disclosed herein can monitor the compression force applied by the compression plates holding the ion-exchange systems and devices together.