Abstract: An electrodialysis apparatus includes a sample chamber including first and second dialysis membranes and filled with a sample between the first dialysis membrane and the second dialysis membrane, an anode chamber including an anode and filled with a first chamber solution between the anode and the first dialysis membrane, and a cathode chamber including a cathode and filled with a second chamber solution between the cathode and the second dialysis membrane. In particular, when a voltage is applied to the anode and the cathode, ionic materials of the sample move to the anode and cathode chambers.

Abstract: An apparatus to treat an influent solution comprising ions to obtain a selectable ion concentration in an effluent solution. The apparatus comprises an electrochemical cell comprising a housing comprising first and second electrodes. A water-splitting ion exchange membrane is between the first and second electrodes, the membrane comprising ananion exchange surface facing the first electrode, and an cation exchange surface facing the second electrode, or vice versa. The housing also has an influent solution inlet and an effluent solution outlet with a solution channel that allows influent solution to flow past both the anion and cation exchange surfaces of the water-splitting ion exchange membrane to form the effluent solution. A variable voltage supply is capable of maintaining the first and second electrodes at a plurality of different voltages during an ion exchange stage.

Abstract: A liquid treatment process is described for sequential removal of ionic species of progressively decreasing ionic strength without precipitation or “scaling.” An aspect of the invention includes two or more electrodeionization operations within one or more electrodeionization stacks. The first electrodeionization operation is performed at a voltage calculated to remove strongly ionized species such as calcium and magnesium from the feed water without scaling. The product of the first electrodeionization operation is then subjected to a second electrodeionization operation. The second electrodeionization operation is performed at a voltage the same as the first electrodeionization operation, and is designed to remove more weakly ionized species such as silica and carbon dioxide, preventing scaling. More than two successive electrodeionization operations may be performed if desired. Multiple electrodeionization operations may occur in a single electrodeionization stack or in multiple electrodeionization stacks.

Abstract: A method and apparatus for connecting water treatment devices is provided. Connecting brackets may allow for a multiple configurations of water treatment devices and can simplify the building of water treatment systems.

Abstract: EDI apparatus for demineralizing a liquid flow is assembled in a housing having a cylindrical shape, and includes two metal electrodes, and one or more leafs, each leaf comprising a pair of selectively ion-permeable membranes arranged parallel to each other and spaced apart by spacing elements that allow liquid to flow in the interstitial space between membranes, thus forming an arrangement of dilute and concentrate cells in a desired flow configuration. Spacing elements between membranes, as well as between leaves, can be formed of inert polymer material, ion exchange beads, ion exchange fibers, a combination of two or more these elements, or a porous media incorporating one or more of such elements as an intrinsic part. An inner or central electrode and an outer or perimeter electrode establish a generally uniform and radially-oriented electrical or ionic current between the inner and the outer electrodes, across the helical flow spaces defined by the membrane/spacer windings.

Abstract: An electrokinetic method and apparatus for discretely collecting ionic contaminants from a variety of media, with an ionic current there across in which an ion collection compartment has been positioned. Each compartment preferably compromises of an anion or cation exchange membrane and a solution that provides an accumulation zone for ions that permeate into the compartment. After the collection period, the solution is extracted from the compartment, and the concentration of ionic contaminants is determined using standard analytical methods. The preferred apparatus embodiment for use in conjunction with such a method has a direct-push probe configuration. The apparatus can be used (a) to detect low concentrations of ionic contaminants, (b) to evaluate cleanup efficiencies, and (c) to monitor the transport of ionic contaminants.

Abstract: An electrodeionisation apparatus comprising, successively: means defining an anode chamber, means defining one or more anion exchange chambers, means defining one or more mixed exchange chambers, means defining one or more cation exchange chambers, and means defining a cathode chamber, the anion, mixed and cation exchange chambers providing a flow path for water to be purified, is described. The present invention incorporates advantages of both separate resin bed and mixed resin bed technology.

Abstract: A stabilizing DC current interface for an electro-deionization (EDI) water purifying module. Each EDI module comprises anionic/cationic membranes, a center pipe, nets/spacers in concentrate/dilute water chambers and an anode and cathode for coupling to the stabilizing DC current interface. Because a stabilized DC current is provided by the interface, the power to each EDI module is not influenced by water temperature, flow rate, water quality in the module, thereby providing a stabilized quality product water while saving energy. A plurality of EDI modules can be operated in electrical series using a DC current interface resulting in reduced DC power consumption.

Abstract: An electrodeionization apparatus is provided, in which enough electric current flows even when voltage applied between the electrodes is low, thereby sufficiently performing deionization. A single first cation exchange membrane, a single anion exchange membrane, a single second cation exchange membrane are arranged between a cathode and an anode so that a concentration-cathode compartment, a desalting compartment, a concentrating compartment, and an anode compartment are formed, in this order, between the cathode and the anode. The concentration-cathode compartment and the anode compartment are filled with a cation exchange resin, respectively. The desalting compartment is filled with a mixture of the cation exchange resin and an anion exchange resin. Fed into the anode compartment is raw water or deionized water. Water from the anode compartment is sent to the concentrating compartment and the concentration-cathode compartment sequentially.

Abstract: The invention relates to apparatus and methods for generating and recycling fluorine. The applicants recognized that a fluorine separator, used either alone or in combination with a plasma generator can produce sufficient quantities of fluorine at its point of use for thin film processing. The fluorine separator can take the form of a condenser, a membrane separation device, a fluorine ion conductor comprising a solid electrolyte, or a combination of the foregoing. In some embodiments, reaction products comprising fluorine are passed to the fluorine separator. In other embodiments, separated fluorine is passed, either alone or in conjunction with additional feed stock comprising fluorine, to a plasma generator. The fluorine separator allows fluorine to be recycled and waste products to be eliminated from the system.

Abstract: In the electrodeionization deionized water producing apparatus, water is passed through a deionizing chamber(s) packed with an organic porous ion exchange material having a three-dimensional network structure to remove ionic impurities in the water, thereby producing deionized water. At the same time, a DC electric field is applied to the deionizing chamber(s) to discharge ionic impurities adsorbed on the organic porous ion exchange material outside the system, wherein the DC electric field is applied so that the ions to be discharged may electrophoretically move in the direction reverse to the flow of water through the organic porous ion exchange material.

Abstract: A method of and apparatus for continuously making an organic ester from a lower alcohol and an organic acid is disclosed. An organic acid or salt is introduced or produced in an electrode ionization (EDI) stack with a plurality of reaction chambers each formed from a porous solid ion exchange resin wafer interleaved between anion exchange membranes or an anion exchange membrane and a cation exchange membrane or an anion exchange membrane and a bipolar exchange membranes. At least some reaction chambers are esterification chambers and/or bioreactor chambers and/or chambers containing an organic acid or salt. A lower alcohol in the esterification chamber reacts with an anion to form an organic ester and water with at least some of the water splitting with the ions leaving the chamber to drive the reaction.

Abstract: The dilute support frame is made up of interphase longitude and latitude bars that preferably are hollow. The bars can be rectangular, rectangular with a rounded end, half-circular, triangular, polygonal or any combination thereof. The bars are sized to support the ion exchange resin in the dilute channel adjacent the concentrate membrane bag. The support frame also assures fluent water flow in the dilute channel. The support frames are arrayed on the membranes with interphase aisle to save the frame arrays and make water flow fluently. The membrane envelopes in turn with the support frames as both are preferably wound to form the cylinder module, and is covered by one plastic protecting net. This new type of support frame can assure fluent water flow in dilute channels and convenient resin filling.

Abstract: The resin seepage-proof spiral would Electrodeionization (EDI) module includes anion and cation ion exchange membranes, concentrate and dilute distributing channels, net sheets inside of the channels, positive and negative electrodes and an EDI housing. The housing includes an insulation shell and covers. The multiple layers of anion and cation ion exchange membranes concentrate and dilute water distributing channels and net sheets are wound around a negative electrode pipe centered in the EDI module. The negative electrode pipe is arranged to collect concentrate water inside of the pipe. A circularity positive electrode is located outside the wound membranes and within the insulation shell, which is generally cylindrical in shape. Inside the cylindrical housing, the dilute water distributing channel is filled by ion exchange resin. The EDI module includes two inserts of multiple holed material layer, one on each end of the module.

Abstract: Apparatus and method are disclosed for introducing ion exchange or other particulates into compartments of an already-assembled electrodeionization or comparable stack by modulating a flow of slurry into the compartments with slugs of gas such as air. The air propels liquid through the cells, scavenging ponded liquid so that the particulates (which are retained, e.g., by a strainer or obstruction, in compartment of the apparatus) are deposited as well-packed beds to fill the compartments. Pressurized air filling protocols may deliver discrete slugs of slurry between bursts of air, and the direction of filling may be periodically reversed to diminish particle bed non-homogeneities or settling gradients that arise during transport. The slugs of air may be applied in the direction of slurry flow, in the reverse direction, or both. Different slurries may be transported in a sequence to form layered and packed beds of enhanced utility.

Abstract: The electrodeionization water producing apparatus comprising a depletion chamber packed with an ion exchange material, the depletion chamber being partitioned by a cation exchange membrane on one side and an anion exchange membrane on the other side, and concentrate chambers installed on both sides of the depletion chamber with the cation exchange membrane and the anion exchange membrane disposed inbetween, the depletion chamber and the concentrate chambers disposing between an anode chamber equipped with an anode and a cathode chamber equipped with a cathode, wherein the concentrate chambers are packed with an organic porous ion exchange material having a continuous pore structure in which the wall made from interconnected macropores contains mesopores with an average diameter of 1 to 1,000 ?m. The apparatus ensures reduction of electric resistance and does not form scale in the concentrate chamber during long continuous operation.

Abstract: An EDI device includes a composite electrode enclosed within the cylinder shell of the device. The EDI inner module preferably has one concentrate center pipe as the electrode in the center axis and at least one layer of anion/cation exchange membranes and a support frame in concentrate/dilute chambers wound around the center pipe. The electrode plate is inside the encircled cylindrical shell (isolating vessel). It is connected to an electrical contact plate located in the shell. Either the anode or cathode can be set in the center pipe, and the other electrode can be set in the vessel or shell lining. The electrical contact plate also contacts an electrical contact reed located on the vessel cover when the cover is connected to the shell. The electrical contact plate provides a reliable conductive bridge between the contact reed and the electrode plate and thus passes DC from the contact reed to the electrode plate.

Abstract: In a device for electro-deionization (EDI) in the demineralization of aqueous solutions, which device includes ion exchange membranes arranged alternately and in spaced relationship so that between the membranes compartments are formed of which at least some are filled with cation and anion resin exchange particle fractions forming a mixed bed ion exchanger, the ion exchange resin particles of one of the two fractions include a magnetic material and a magnetic field generator is provided for generating a field for orienting the magnetic resin particles and arranging them in parallel chains extending between the membranes.

Abstract: Injection bonded articles comprised of a rigid core and secured together with an elastomeric material network which also forms seals and encapsulates at least a portion of the rigid core. The elastomeric material is selected to be compatible with the material comprising the rigid core to create a chemical and mechanical bond therebetween. Injection bonding and over-molding techniques are used to fabricate an electrodeionization apparatus spacer comprised of mated rigid segments secured by a unitary elastomeric material network that also forms internal and external seals that fluidly isolate one or more of inlet ports, resin cavities, and outlet ports as well as throughports. Injection bonding and over-molding techniques can also be used to fabricate other articles comprised of multiple segments.

Abstract: An apparatus for removing charged contaminants from a water stream. The apparatus can be figured to provide the decontaminated water stream to an analytical system. Methods of use of the same are also disclosed.

Abstract: An electrodeionization device for large-volume ultra-pure deionization of water is disclosed. The device comprises a plurality of alternating ion depletion and concentration compartments, interposed between an anode assembly and a cathode assembly, through which flows either a product stream or a waste stream. Each compartment contains several fluid-accessible channels packed with an appropriate ion-exchange medium. The flow of the waste and product streams among the compartments is “parallel” (i.e., contemporaneous). The flow of a stream through the compartments—i.e., through the channels therein—is “serial” (i.e., sequential). In an embodiment, electrical current is generated through the compartments using segmented electrodes—either in the anode and/or the cathode assembly—that are connected to a single multiple-outlet power source.

Abstract: Silica and boron are particularly removed at high rate in processing by the electrodeionization apparatus. An electrodeionization apparatus has an anolyte compartment 17 having an anode 11, a catholyte compartment 18 having a cathode 12, concentrating compartments 15, and desalting compartments 16. The concentrating compartments 15 and the desalting compartments 16 are alternately formed between the anolyte compartment 17 and the catholyte compartment 18 by alternately arranging a plurality of anion-exchange membranes 13 and a plurality of cation-exchange membranes 14. The desalting compartments 16 and the concentrating compartments 15 are filled with ion-exchanger. The anion exchanger/cation exchanger volume ratio is 8/2 to 5/5. Electrode water flows into the anolyte compartment 17 and the catholyte compartment 18. Concentrated water is introduced into the concentrating compartments 15. Raw water is fed into the desalting compartment 16 to produce the deionized water from the desalting compartment 16.

Abstract: In a device for electro-deionization (EDI) in the demineralization of aqueous solutions, which device includes ion exchange membranes arranged alternately and in spaced relationship so that between the membranes compartments are formed of which at least some are filled with cation and anion resin exchange particle fractions forming a mixed bed ion exchanger, the ion exchange resin particles of one of the two fractions include a magnetic material and a magnetic field generator is provided for generating a field for orienting the magnetic resin particles and arranging them in parallel chains extending between the membranes.

Abstract: An electrodeionization apparatus comprising an endblock formed from a resilient material, and method for making the same. The resilient material may include various types of thermoplastic elastomers, such as, styrene block copolymers, copolyesters, plolyurethanes, polyamides, thermoplastic elastomeric olefins, and thermoplastic vulcanizates. The resilient material may have a Shore A hardness of between about 40 and about 90.

Abstract: A composite ion exchanger with ion exchange groups uniformly dispersed therein, comprising a porous polymer having a continuous pore structure, which comprises interconnected macropores and mesopores existing on the walls of the interconnected macropores, having a total pore volume of 1 to 50 ml/g, and a dense layer covering at least one surface of the porous polymer and integrally formed with the porous polymer. The structure provides a body integrally formed from a material functioning as an ion exchange membrane and a material functioning as an ion exchanger and allows the material functioning as an ion exchanger to have an extremely large pore volume and specific surface area. Electric power saving is possible if the product is used as an electrodeionization module for an electrodeionization water purification device.

Abstract: Method and apparatus for suppressed ion analysis in which a sample solution of analyte (e.g., anion) in an eluent of electrolyte counterions (e.g., sodium), is chromatographically separated. Then, the counterions are suppressed in a suppression zone and removed and used to convert the analyte ions to salt form in a salt-converting zone. The suppression and salt-converting zones may be contiguous or remote, and may be performed in devices of the membrane suppresser type. Thereafter, the salts or acids or bases formed from them (e.g., in membrane suppressor devices) are detected. Also, salt conversion can be performed using two ion exchange packed bed salt convertors in which one bed is on-line while the other is regenerated, followed by a reversal of flow.

Abstract: The resin seepage-proof spiral would Electrodeionization (EDI) module includes anion and cation ion exchange membranes, concentrate and dilute distributing channels, net sheets inside of the channels, positive and negative electrodes and an EDI housing. The housing includes an insulation shell and covers. The multiple layers of anion and cation ion exchange membranes concentrate and dilute water distributing channels and net sheets are wound around a negative electrode pipe centered in the EDI module. The negative electrode pipe is arranged to collect concentrate water inside of the pipe. A circularity positive electrode is located outside the wound membranes and within the insulation shell, which is generally cylindrical in shape. Inside the cylindrical housing, the dilute water distributing channel is filled by ion exchange resin. The EDI module includes two inserts of multiple holed material layer, one on each end of the module.

Abstract: An electrodeionization apparatus and method for purifying a fluid. A fluid, such as water, can be purified by removing weakly ionizable species from the fluid. Weakly ionizable species may be dissociated at different pH levels to facilitate removal from the fluid in an electrodeionization device.

Abstract: An electrodeionization apparatus has an anolyte compartment 17 having an anode 11, a catholyte compartment 18 having a cathode 12, concentrating compartments 15, and desalting compartments 16. The concentrating compartments 15 and the desalting compartments 16 are alternately formed between the anolyte compartment 17 and the catholyte compartment 18 by alternately arranging a plurality of anion-exchange membranes 13 and a plurality of cation-exchange membranes 14. The desalting compartments 16 are filled with ion-exchanger and the concentrating compartments 15 are filled with ion-exchanger, activated carbon, or electric conductor. Electrode water flows into the anolyte compartment 17 and the catholyte compartment 18. Concentrated water is introduced into the concentrating compartments 15. Raw water is fed into the desalting compartment 16 to produce the deionized water from the desalting compartment 16.

Abstract: An EDI device includes a composite electrode enclosed within the cylinder shell of the device. The EDI inner module preferably has one concentrate center pipe as the electrode in the center axis and at least one layer of anion/cation exchange membranes and a support frame in concentrate/dilute chambers wound around the center pipe. The electrode plate is inside the encircled cylindrical shell (isolating vessel). It is connected to an electrical contact plate located in the shell. Either the anode or cathode can be set in the center pipe, and the other electrode can be set in the vessel or shell lining. The electrical contact plate also contacts an electrical contact reed located on the vessel cover when the cover is connected to the shell. The electrical contact plate provides a reliable conductive bridge between the contact reed and the electrode plate and thus passes DC from the contact reed to the electrode plate.

Abstract: In the electrodeionization deionized water producing apparatus, water is passed through a deionizing chamber(s) packed with an organic porous ion exchange material having a three-dimensional network structure to remove ionic impurities in the water, thereby producing deionized water. At the same time, a DC electric field is applied to the deionizing chamber(s) to discharge ionic impurities adsorbed on the organic porous ion exchange material outside the system, wherein the DC electric field is applied so that the ions to be discharged may electrophoretically move in the direction reverse to the flow of water through the organic porous ion exchange material.

Abstract: An electrodeionization apparatus and method for purifying a fluid. A fluid, such as water, can be purified by removing weakly ionizable species from the fluid. Weakly ionizable species may be dissociated at different pH levels to facilitate removal from the fluid in an electrodeionization device.

Abstract: A system for decontamination of radioactive components includes an acidic decontamination solution which is exposed to radioactive components to remove a layer of contaminated material and an ion exchange cell which removes the radioactive contamination from the decontamination solution. The ion exchange cell has cathode, anode and central compartments. The decontamination solution flows into the central compartment and the radioactive cations in the solution are drawn towards the cathode. The acidity in the cathode chamber is controlled so that small radioactive metal particles are deposited on the cathode. A cathode solution flows over the cathode which removes the deposited radioactive particles. The cathode solution and small particles flow into a waste collection container where the metal particles settle to the bottom of the container where they are easily separated from the solution. The only waste product produced by the system are the small radioactive metal particles which are easily disposed of.

Abstract: An apparatus for removing charged contaminants from a water stream. The apparatus can be figured to provide the decontaminated water stream to an analytical system. Methods of use of the same are also disclosed.

Abstract: The electrodeionization water producing apparatus comprising a depletion chamber packed with an ion exchange material, the depletion chamber being partitioned by a cation exchange membrane on one side and an anion exchange membrane on the other side, and concentrate chambers installed on both sides of the depletion chamber with the cation exchange membrane and the anion exchange membrane disposed inbetween, the depletion chamber and the concentrate chambers disposing between an anode chamber equipped with an anode and a cathode chamber equipped with a cathode, wherein the concentrate chambers are packed with an organic porous ion exchange material having a continuous pore structure in which the wall made from interconnected macropores contains mesopores with an average diameter of 1 to 1,000 &mgr;m. The apparatus ensures reduction of electric resistance and does not form scale in the concentrate chamber during long continuous operation.

Abstract: A bipolar membrane which exhibits a low water dissociation voltage for an extended period of time under a high current density condition, and a high current efficiency, without developing blister. The bipolar membrane comprises a cation-exchange membrane and an anion-exchange membrane which are joined together, wherein ion-exchange resin particles having ions exchanged with ions of a metal of an atomic number 20 to 90, such as titanium, zirconium, tin, iron, ruthenium or palladium, or with complex ions of said metal are existing on the junction interface between the cation-exchange membrane and the anion-exchange membrane.

Abstract: Feed water, fed through an inlet 6 into a desalting compartment 8, flows around the end 4a of a anion-exchange membrane 4 surrounding an anode 2a. The feed water enters into a portion defined between the anion-exchange membrane 4 and a cation-exchange membrane 5, and flows around the end 5a of the cation-exchange membrane 5 surrounding a cathode 3a. Then, the water to be treated further flows around the ends 4b, 5b of ion-exchange membranes 4, 5 surrounding an anode 2b and a cathode 3b, respectively, and then flows out through a product water outlet 7. A part of product water is supplied to the concentrated water circulating within the concentrating compartment 30, 40. A part of the concentrated water flowing out of the concentrating compartment 30, 40 is added to concentrated water circulating within the concentrating compartment 10, 20. The diffusion of silica from the concentrating compartment is restricted. As a result, final product water containing extremely low silica concentration is obtained.

Abstract: An electrodeionization apparatus in which enough electric current flows even when a low voltage is applied, so that it can made sufficient deionizing treatment is provided. A cation exchange membrane 3 and an anion exchange membrane 4 are arranged between a cathode 1 and an anode 2, a cathode-concentration compartment 5 is formed between the cathode 1 and the cation exchange membrane 3, an anode-concentration compartment 6 is formed between the anode 2 and the anion exchange membrane, and a desalting compartment 7 is formed between the cation exchange membrane 3 and the anion exchange membrane 4. The cathode-concentration compartment 5 and the anode-concentration compartment 6 each of which is used also as a concentrating compartment are filled with a cation exchange resin 8. The desalting compartment 7 is filled with a mixture of the cation exchange membrane 8 and an anion exchange membrane 9. Raw water is fed into the desalting compartment 7 and taken out as deionized water.

Abstract: An electrodeionization apparatus and method of use includes an expanded conductive mesh electrode. The expanded conductive mesh electrode may be formed from any conductive material that is dimensionally stable and may be coated with conductive coating suitable for use in anode or cathode service. The expanded conductive mesh electrodes are formed by slitting a sheet of metal and pulling its sides in a direction perpendicular to the slits. The fabricated mesh may be flattened after stretching. The expanded conductive mesh electrodes typically have a diamond-shaped pattern of any size that provides support for an adjacent ion-permeable membrane while allowing an electrode or fluid stream to flow through. The mesh size typically has a long-wise dimension and a short-wise dimension. The conductive mesh electrode may also be placed against an endblock having fluid channels. These channels may be serpentine or parallel channels, which allow fluid flow to wash away any accumulation.

Abstract: Electrodeionization apparatus and method. The electrodeionization apparatus includes an ion-depleting compartment in which alternating layers of an electroactive media are positioned. One of the alternating layers is doped to provide a more balanced current distribution through the apparatus. The method involves providing reducing the difference in conductivity between the alternating layers positioned in the ion-depleting compartment by adding a dopant material to one of the layers.

Abstract: For dosing lithium in cooling water containing cationic impurities or for reducing cationic impurities, the invention guides cooling water cycle through a first side of an electrodialysis unit and guides a concentration cycle through a second side of the electrodialysis unit. Cationic impurities are filtered out of the medium of the concentration cycle with a selective ion exchanger that is disposed in the concentration cycle.

Abstract: An electrodeionization apparatus and method for purifying a fluid. A fluid, such as water, can be purified by removing weakly ionizable species from the fluid. Weakly ionizable species may be dissociated at different pH levels to facilitate removal from the fluid in an electrodeionization device.

Abstract: An electrodeionisation apparatus comprising a first deionising flow path and an integral second deionising flow path is described. The outflow from the first path is held in a holding tank prior to passage through the second flow path, and the outflow from the second path is available for use. Optionally, the second path outflow is partly or fully returned to the holding tank. Me recirculation of the already purified water in the holding tank maintains the water in the holding tank at a higher standard than otherwise “standing” purified water. The water in the holding tank could be separately made available for use. The apparatus requires the use of only a single pair of electrodes and hence one power supply. Moreover, the ion exchange materials in the first deionising flow path can be regenerated when water is not flowing through them such that they have a greater capacity for deionisation when required.

Abstract: An electro-regenerating type apparatus for producing deionized water, which comprises an electrodialyzer having cation exchange membranes and anion exchange membranes alternately arranged between an anode compartment provided with an anode and a cathode compartment provided with a cathode, demineralizing compartments compartmentalized with the anion exchange membranes on the anode side and compartmentalized with the cation exchange membranes on the cathode side, and concentrating compartments compartmentalized with the cation exchange membranes on the anode side and compartmentalized with the anion exchange membranes on the cathode side, the electrodialyzer having ion exchangers accommodated in the demineralizing compartments, wherein a porous anion exchanger layer having a porosity of from 20 to 95%, a maximum pore size of from 0.01 to 500 &mgr;m and a thickness of at least five times the maximum pore size and from 10 &mgr;m to 10 mm, is provided on the anode side of each anion exchange membrane.

Abstract: An electrodeionization (EDI) module is formed an anode spaced apart from a cathode, one or more waste channels formed between the electrodes and a product channel located inward of the waste channel(s). Ion permeable membranes form the boundary between the product channel and the waste channel(s). The product channel and waste channels are filled with a mixture of anionic and cationic ion exchange materials. At least the waste channel(s) and preferably the product channel as well, use either an anion bead having a relatively low affinity for the selected anion specie(s) to be retained (e.g. Type II) or it is a blend with Type I materials. Preferably, the membranes contain an ion exchange material to speed the transfer of ions across them. More preferably, the anionic membrane contains anion materials that have a relatively low affinity for the selected specie or species for retention.

Abstract: An electrodeionization apparatus has an anolyte compartment 17 having an anode 11, a catholyte compartment 18 having a cathode 12, concentrating compartments 15, and desalting compartments 16. The concentrating compartments 15 and the desalting compartments 16 are alternately formed between the anolyte compartment 17 and the catholyte compartment 18 by alternately arranging a plurality of anion-exchange membranes 13 and a plurality of cation-exchange membranes 14. The desalting compartments 16 are filled with ion-exchanger and the concentrating compartments 15 are filled with ion-exchanger, activated carbon, or electric conductor. Electrode water flows into the anolyte compartment 17 and the catholyte compartment 18. Concentrated water is introduced into the concentrating compartments 15. Raw water is fed into the desalting compartment 16 to produce the deionized water from the desalting compartment 16.

Abstract: An electric deionizing apparatus comprising a first and a second electric deionizing apparatus arranged in series, in which water is deionized by the first electric deionizing apparatus and then deionized by the second electric deionizing apparatus, and a means for adding an aqueous electrolyte solution into water released from the first electric deionizing apparatus and which is supplied into the second electric deionizing apparatus. A process for electric deionization comprising supplying water to a first electric deionizing apparatus, deionizing the water in the first electric deionizing apparatus, adding an aqueous electrolyte solution to the deionized water, supplying the deionized water to a second electric deionizing apparatus and deionizing the supplied deionized water in the second electric deionizing apparatus. Silica and boron components in the water are effectively removed to obtain deionized water having a high resistivity.

Abstract: An electrochemical ion exchange cell comprises a metal carbollide as ion exchange material. The carbollide is preferably a polynuclear cobalt dicarbollide and is typically substituted by chlorine. Also novel are polynuclear metal carbollides comprising a substituted carbollide cage, as well as metal carbollides comprising a carbollide cage substituted by a moiety having a —COOH or —SH group.

Abstract: An electrodeionization apparatus includes an anode; a cathode; cation-exchange membranes and anion-exchange membranes alternately arranged between the anode and the cathode; desalting compartments and concentrating compartments arranged alternately to be located between the cation-exchange membrane and the anion-exchange membrane; and partition members situated in the respective desalting compartments to form cells therein. The partition member has inclined portions inclined obliquely relative to a longitudinal direction of the desalting compartment to define the cells laterally and vertically. Thus, one cell faces obliquely at least one of the cells adjacent thereto to allow water to flow obliquely between the one cell and the at least one of the cells. An ion exchanger is filled in the respective cells. The ion exchanger do not pass through the partition member.

Abstract: Electrodeionization apparatus and method. The electrodeionization apparatus includes an ion-depleting compartment in which alternating layers of an electroactive media are positioned. One of the alternating layers is doped to provide a more balanced current distribution through the apparatus. The method involves providing reducing the difference in conductivity between the alternating layers positioned in the ion-depleting compartment by adding a dopant material to one of the layers.