Abstract: A system and method is disclosed for recovering reagents that are used in removing contaminants from a flue gas stream. The system and method includes contacting the flue gas stream with reagents such as ammonia and sulfuric acid to create an ammonium sulfate stream. The ammoniated sulfate stream is forwarded to an electrodialysis unit wherein the reagents are regenerated and recirculated back to the system.

Abstract: An acid component removal device for removing an acid component from an acid gas absorbent containing an amine, comprising: an anode; a cathode; and an electrodialysis structure having four compartments formed by arranging an first membrane which is either an anion exchange membrane or a cation exchange membrane, a second membrane which is a bipolar membrane, and a third membrane which is either an anion exchange membrane or a cation exchange membrane and which is the other of the first membrane, in this order, from the anode end to the cathode end between the anode and the cathode, with a space each between the membranes.

Abstract: Methods and systems for electrochemical conversion of carbon dioxide to organic products including formate and formic acid are provided. A method may include, but is not limited to, steps (A) to (C). Step (A) may introduce an acidic anolyte to a first compartment of an electrochemical cell. The first compartment may include an anode. Step (B) may introduce a bicarbonate-based catholyte saturated with carbon dioxide to a second compartment of the electrochemical cell. The second compartment may include a high surface area cathode including indium and having a void volume of between about 30% to 98%. At least a portion of the bicarbonate-based catholyte is recycled. Step (C) may apply an electrical potential between the anode and the cathode sufficient to reduce the carbon dioxide to at least one of a single-carbon based product or a multi-carbon based product.

Abstract: The present disclosure provides a membrane having a first major surface and a second major surface and including one or more anionic exchange electrolyte polymers. The membranes can be useful for selectively mass transporting molecules and/or ions.

Abstract: A filter unit may include an electrode structure, a fluid-purifying flow path, and a pH adjusting chamber. The electrode structure may include a cathode, a cation exchange membrane, an anion exchange membrane, and an anode in that order. The fluid-purifying flow path may be at least one of a path in the cathode, between the cathode and the cation exchange membrane, between the anion exchange membrane and the anode, and in the anode. The fluid-purifying flow path may include an adsorption function. The pH adjusting chamber may be between the cation exchange membrane and the anion exchange membrane. The pH adjusting chamber may be configured to control the pH of the fluid in the fluid-purifying flow path.

Abstract: The present invention relates to a process comprising the reaction of a cyanide with a hydrogen cyanide-reactive compound, characterized in that the cyanide is a cyanide salt and the process is an electrochemical process involving the transporting of a reaction mixture to which cyanide salt has been added through an electrochemical cell, in which process the cyanide salt reacts with the hydrogen cyanide-reactive compound while at least partly under the influence of an electric current the cyanide salt is acidified and the salt cation content is reduced.

Abstract: A method for continuously manufacturing lithium transition metal phosphates of the formula LiMPO4, comprising the steps of providing an aqueous reaction mixture containing LION, H3PO4, and a transition metal sulphate, converting the reaction mixture into a lithium transition metal phosphate, separating the solid lithium transition metal phosphate from the soluble part of the reaction mixture, subjecting the soluble part (diluate) to an electrodialysis, and isolating the part of the electrodialysate that contains an aqueous LiOH solution.

Abstract: A process for producing a gas using an electrodialysis apparatus includes flowing at least two solutions and an electrode solution into the apparatus, pressurizing the apparatus at a stack pressure, applying a voltage to the apparatus's electrodialysis stack so a dissolved gas is generated in the second solution, flowing the second solution out of the apparatus, regenerating the gas out of the second solution, and collecting the gas. A process for generating a product, like a gas, liquid, or supercritical fluid, using an electrodialysis apparatus includes flowing at least two solutions and an electrode solution into the apparatus, adjusting the temperature and pressure so the product will be generated from the second solution, applying a voltage to the electrodialysis stack of the apparatus so that the product is generated in the second solution, flowing the second solution out of the apparatus, and regenerating the product from the second solution.

Abstract: A method of water treatment comprising: providing an electrolysis device comprising an electrolysis vessel; providing feed streams to the first salt water chamber of the vessel, second salt water chamber of the vessel, acidic chamber of the vessel, and alkalic chamber of the vessel, the acidic chamber producing an acidic solution and the alkalic chamber producing an alkalic solution; directing at least a portion of the contents of the first and second salt water chambers into a precipitation tank; directing at least a portion of the alkalic solution into the precipitation tank, thereby increasing the pH in the precipitation tank to produce precipitate; and removing the precipitate from the precipitation tank.

Abstract: Method for the removal of ions and ionizable substances from a polar liquid (10) comprising at least one process wherein said polar liquid (10) is split into a first stream (F1) and a second stream (F2), Said first stream (F1) passing through an electrochemically regenerable ion-exchange material (2) located where an electric field between two electrodes (4, 5) is applied, said first stream (F1) flowing from one electrode (4) to the other electrode (5) so that the ions to be removed are migrating in the direction reverse to the first stream flow through said ion-exchange material (2), Said second stream (F2) rinsing said one electrode (4), and said material is regenerated by the ions which are formed at the other electrode (5). Device in particular for the implementation of said method.

Abstract: Electrochemical devices and methods for water treatment are disclosed. An electrodeionization device (100) may include one or more compartments (110) containing an ionselective media, such as boron-selective resin (170). Cyclic adsorption of target ions and regeneration of the media in-situ is used to treat process water, and may be driven by the promotion of various pH conditions within the electrochemical device.

Abstract: Provided is a cleaning process of producing lactic acid. Firstly saccharification liquid is prepared through saccharated materials, then fermented with nutritive materials and lactic acid bacteria, and liquid alkali is used to adjust the pH. The fermentation broth is filtrated with porous membrane, and the lactic acid bacteria in the interception liquid are then reintroduced into the porous membrane for recycling. The permeate from porous membrane is subjected to nanofiltration to be decolored and purified. The concentrated solution from nanofiltration and the cleaning liquid from fermentation tank and its affiliated equipment are filtrated and sterilized by using ceramic membrane, and then are reintroduced into the fermentation unit for recycling. The permeate from nanofiltration is then subjected to bipolar electrodialysis system to prepare lactic acid, and the liquid alkali produced at the same time is reintroduced into the fermentation tank for recycling.

Abstract: A system and method for recovery of CO2 includes an aqueous capture device having a capture solution. The aqueous capture device is arranged to receive gas and to capture components from the gas including at least CO2. An electrodialysis unit in operative connection with the capture device performs an electrodialysis operation on the capture solution including at least the CO2, wherein a CO2 rich process stream and a regenerated capture solution are generated from the capture solution including at least the CO2. The CO2 rich process stream is a pressurized process stream at a pressure which maintains the CO2 substantially within the CO2 rich process stream, while in the electrodialysis unit. In another alternative, at least the pH of the capture stream is controlled.

Abstract: An apparatus and method for abating scale formation during the purification and demineralization of water in an electrochemical deionization apparatus. In the apparatus and method, scale forming ions in a raw water feed are precipitated at a controlled location remote from the deionization chambers of the deionization apparatus. Concentrate water produced during the deionization process to produce demineralized product water is acidified and circulated through the deionization apparatus to prevent scale formation and build-up in the deionization apparatus.

Abstract: To prevent biological fouling in an electrodialysis device, an electrodialysis device including a membrane electrolysis stack are created. Every membrane electrolysis stack comprises membranes stacked on top of each other and respectively dilute and concentrate compartments arranged therebetween, at least one first and at least one second membrane alternating in succession in the membrane electrolysis stack. At least one first membrane is selected from a group comprising an anion exchange membrane and a bipolar membrane, and at least one second membrane is selected from a group comprising a monoselective anion exchange membrane, a monoselective cation exchange membrane and a proton-selective exchange membrane, with the proviso that the membranes are respectively selected independently of each other and that at least one first membrane in the membrane electrolysis stack is a bipolar membrane.

Abstract: A method for selectively removing hydrogen sulfide and carbon dioxide from sour gas by reacting the hydrogen sulfide and carbon dioxide in the sour gas with sodium hydroxide is disclosed. Also disclosed is a process for the production of a salt product from a sour gas stream. The reaction with sodium hydroxide creates a scrubber solution comprising water, hydrocarbons, contaminants and salts. The scrubber solution may be oxidized, filtered and can then be subjected to electrodialysis. Ammonia is introduced into the acid compartments of the cell. Sodium hydroxide and a salt product comprising ammonium sulfate or ammonium thiosulfate with ammonium bicarbonate, ammonium carbonate, ammonium carbamate may be produced. The regenerated sodium hydroxide may be used to sweeten further sour gas. The salt product may be used as a fertilizer.

Abstract: The invention includes novel anion exchange membranes formed by in situ polymerization of at least one monomer, polymer or copolymer on a woven support membrane and their methods of formation. The woven support membrane is preferably a woven PVC membrane. The invention also includes novel cation exchange membranes with or without woven support membranes and their methods of formation. The invention encompasses a process for using the membranes in electrodialysis of ionic solutions and in particular industrial effluents or brackish water or seawater. The electrodialysis process need not include a step to remove excess ions prior to electrodialysis and produces less waste by-product and/or by-products which can be recycled.

Abstract: The object of the present invention is to provide an electrical deionization apparatus capable of long-term operation at a low voltage. To achieve this object, the present invention is directed to an electrical deionization apparatus based on a completely new compartment configuration and provides an electrical deionization apparatus comprising multiple compartments separated by cation- and anion-exchange membranes arranged between anode and cathode, wherein the anion-exchange membrane on the anode side and the cation-exchange membrane on the cathode side together define a water splitting compartment, and wherein an anion deionization compartment defined between anion-exchange membranes is placed on the anode side of the water splitting compartment, and a cation deionization compartment defined between cation-exchange membranes is placed on the cathode side of the water splitting compartment.

Abstract: Process for the manufacture of alkali metal hydroxide, according to which an electrodialysis cell containing three compartments is used, an aqueous alkali metal halide solution is circulated in a saline compartment of the cell, delimited between an anionic membrane and a cationic membrane, an alkali metal halide is introduced into an acidic compartment of the cell, delimited between the anionic membrane and a cationic face of a bipolar membrane and an aqueous alkali metal hydroxide solution is extracted from an alkaline compartment of the cell, delimited between the cationic membrane and an anionic face of the bipolar membrane.

Abstract: A process is described for purifying an amino acid-containing solution by means of electrodialysis, wherein an amino acid-containing solution is employed which is obtained from the fermentation for producing at least one amino acid.

Abstract: Methods of preparing or purifying onium hydroxides of the elements N, S or P by electrodialysis involve an electrodialysis apparatus comprising one or more cell units, each cell unit comprising a bipolar membrane and an anion-selective membrane, and a bipolar membrane or a cation-selective membrane being located on the anode side between the last anion-selective membrane and the anode.

Abstract: A process is disclosed for removing heat stable amine salts using an electrodialysis process. The process of the present invention can be used to reduce the level of heat stable salts in a lean solvent stream in an acid gas removal process. A base is added to the electrodialysis unit in order to permit the recovery of the heat stable amine salts as salts corresponding to the base added. The purified amine solution can be used again to remove acid gases from a gas stream.

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: Bipolar membrane electrodialysis methods for salt splitting polyvalent metal salts, where the metal cation can form substantially insoluble precipitates in the presence of hydroxyl ions can now be used in recovering acid and base values from a salt streams without precipitates fouling cell operation and causing shutdown. The introduction of an acid to the chamber where metal hydroxides would form inhibits their development or neutralizes formed solids, allowing salt splitting to continue. Salt splitting methods of the invention performed with a three compartment bipolar electrodialysis cell are useful in producing concentrated and purified acid forms, such as 2-keto-L-gluconic acid, H(KLG), a key intermediate in the production of ascorbic acid.

Abstract: An electrodialysis water splitting processes incorporates a chromatographic separation step using an amphoteric ion exchange resin to remove contamination salts from a salt solution feedstream and a base product solution. When the chromatographic column is subsequently eluted with water an effective separation of the components is achieved. The separated pure salt stream is forwarded to an electrodialysis water splitter cell for conversion to acid and base. The base product solution (sodium hydroxide, potassium hydroxide) may be similarly purified by passing through a second chromatographic column also containing an amphoteric resin to separate the base from the salt (recovered salt). The process is also applicable in a chlor-alkali process for acidifying the brine feed to the electrolysis cell and for producing high purity caustic from salt.

Abstract: A process is disclosed for removing heat stable amine salts using an electrodialysis process. The process of the present invention can be used to reduce the level of heat stable salts in a lean solvent stream in an acid gas removal process. A base is added to the electrodialysis unit in order to permit the recovery of the heat stable amine salts as salts corresponding to the base added. The purified amine solution can be used again to remove acid gases from a gas stream.

Abstract: A method for fermentation of lactic acid from a sugar-containing fermentation liquid in a fermentor by means of lactic acid-forming bacteria, in which whey protein is present or is added as a nutrient substrate for the lactic acid-forming bacteria, wherein at least one protease is added to the fermentor during the fermentation, so that hydrolysis of protein to amino acids takes place simultaneously with the fermentation of sugar into organic acid, and wherein lactic acid resulting from the fermentation is isolated from the fermentation liquid. Ammonia is preferably added to result in the formation of ammonium lactate, and lactic acid is preferably isolated by a process comprising ultra filtration, ion exchange, conventional electrodialysis and electrodialysis with bipolar membranes.

Abstract: An apparatus and the process produces salts by an electrodialysis operation. The basic electrodialysis apparatus is a cell having a number of compartments separated by membranes. A DC source is connected to drive a current through a feed stream passing through the cell which splits the salt stream into an acid and a base. The incoming feed may be nanofiltered to remove divalent metal. The base loop may be in communication with an ion exchange column packed with a material that removes multivalent cations. Depending upon the material being processed and the desired end result either or both the nanofiltration and the ion exchanged column may be used in the apparatus.

Abstract: Bases and organic acids are simultaneously separated from aqueous solutions comprising bases and organic acids by electrochemically treating aqueous solutions containing these components, particularly the aqueous waste solution obtained from an aldolization reaction.

Abstract: An apparatus and process produces salts by an electrodialysis operation. The basic electrodialysis apparatus is a cell having a number of compartments separated by membranes. A DC source is connected to drive a current through a feed stream passing through the cell which splits the salt stream into an acid and a base. The incoming feed may be nanofiltered to remove divalent metal. The base loop may be in communication with an ion exchange column packed with a material that removes multivalent cations. Depending upon the material being processed and the desired end result either or both the nanofiltration and the ion exchanged column may be used in the apparatus.

Abstract: The invention uses a stack of three compartment electrodialysis cells in a process for the production amino acid hydrochloride and an alkali. The electrodialysis cell contains bipolar, cation and anion membranes which are arranged to form acid, base and salt compartments. The process begins with supplying a salt solution to the salt compartment, water to the base compartment, and a liquid comprising an amino acid to the acid compartment. Preferably, the feed salt is sodium chloride or potassium chloride or lithium chloride. A direct current driving force is applied across the cell to convert the salt solution to an alkali in the base compartments and an amino acid hydrochloride in the acid compartment. The acid and alkali solutions and a depleted salt solution are withdrawn from their respective compartments. A chelating agent may be added to the salt solution before it is fed into the electrodialysis cell.

Abstract: An electrodialysis method using a bipolar membrane (BP) for regenerating acids, wherein a series of base (B), acid (A) and salt (S) compartments are provided between a positive electrode (anode) and a negative electrode (cathode), said compartments being defined by a series of membranes: cationic, bipolar, anionic, cationic, bipolar and so forth, and a solution being circulated through each compartment. An additional anionic membrane (10) is applied to the anionic side (11) of the bipolar membrane (BP) with no discernible gap therebetween so that contamination of the acid compartment by cations is reduced.

Abstract: Process for the manufacture of a bipolar membrane, according to which an anionic membrane is joined side by side to a cationic membrane, the membranes having been subjected beforehand to a conditioning pretreatment, the conditioning pretreatment of the anionic membrane comprising bringing the latter into contact with a compound of a polyvalent metal and with an aqueous alkali metal hydroxide solution and the conditioning pretreatment of the cationic membrane essentially comprising bringing the said cationic membrane into contact with water which is essentially free from polyvalent metal and from alkali metal. Use of the bipolar membrane thus obtained for the manufacture of aqueous sodium hydroxide solutions by electrodialysis.

Abstract: A process recovers organic acid and ammonia from their salts preferably obtained from microbial fermentation of a saccharide in a nutrient. The fermented materials is passed through a nanofiltration or a chelating resin ion-exchange bed or a combination of both a nanofilter and a chelating resin ion-exchange bed in order to reduce divalent or multivalent metal contaminants. Then, the filtered material is processed in a multi compartment electrodialysis containing bipolar and anion membranes.

Abstract: A method is disclosed for producing di- and more highly oxidized carboxylic acids from a compound selected from a first group consisting of carbohydrates, carbohydrate derivatives and carbohydrate derivatives having more than one primary alcohol group, comprising oxidizing, in an aqueous solution in a concentration between 0.1% and 60%, the compound selected from said first group and a compound selected from a second group consisting of monooxidized carbohydrates, monooxidized carbohydrate derivatives and monooxidized carbohydrate derivatives having more than one primary alcohol group, with one of oxygen and an oxygen-containing gas, on one of a noble metal catalyst and a mixed metal catalyst; electrodialyzing the oxidized compounds in at least one electrodialysis stage; and removing said di- and more highly oxidized carboxylic acids in said at least one electrodialysis stage.

Abstract: A process is described for producing organic acids such as lactic acid. The process includes the steps of producing lactic acid by fermentation, resulting in an aqueous fermentation broth containing lactic acid, and adding a calcium base, such as calcium carbonate, to the fermentation broth, thereby producing calcium lactate in the broth. Biomass is removed from the broth, thereby leaving an aqueous solution or dispersion of calcium lactate. The calcium lactate is reacted with a source of ammonium ions, such as ammonium carbonate, or a mixture of ammonia and carbon dioxide, thereby producing an ammonium lactate. Contaminating cations can be removed by ion exchange. The free lactic acid or a derivative thereof can be separated from the ammonium ions, preferably by salt-splitting electrodialysis.

Abstract: In one embodiment, the invention relates to a process for purifying solutions containing a hydroxide compound, including the steps of: (A) providing an electrochemical cell containing an anode, a cathode, a cation selective membrane and a bipolar membrane, the bipolar membrane having an anion selective side facing the anode and a cation selective side facing the cathode, wherein the cation selective membrane is positioned between the anode and the bipolar membrane, and the bipolar membrane is positioned between the cation selective membrane and the cathode, thereby defining a feed compartment between the cation selective membrane and the anode, a recovery compartment between the bipolar membrane and the cation selective membrane, and a water compartment between the bipolar membrane and the cathode; (B) charging a solution of an ionic compound at a first concentration to the water compartment, and water to the recovery compartment; (C) charging a solution containing the hydroxide compound at a second concentra

Abstract: The invention relates to a process for the separation of lactulose from a mixture of lactulose and lactose in the presence of a weak acid capable of reversibly forming a complex with lactulose, by using an electrodialysis equipment including an anode and a cathode compartment separated by a plurality of parallel compartments comprising alternating diluate and concentrate compartments, wherein adjacent compartments are separated from each other by permselective membranes; which process is characterized by:(a) continuously passing an alkaline aqueous solution of lactulose, lactose and said complex forming weak acid through the diluate compartments, each diluate compartment being bound by a bipolar membrane at its lateral side facing the cathode and at its opposite lateral side by an anion exchange membrane, separating said compartment from its adjacent concentrate compartment;(b) continuously passing a carrier fluid through the concentrate compartments, each concentrate compartment being bound at its lateral si

Abstract: In one embodiment, the invention relates to a process for purifying solutions containing a hydroxide compound, including the steps of: (A) providing an electrochemical cell containing an anode, a cathode, a cation selective membrane and an anion selective membrane, wherein the cation selective membrane is positioned between the cathode and the anion selective membrane, and the anion selective membrane is positioned between the cation selective membrane and the anode, thereby defining a feed compartment between the cation selective membrane and the anion selective membrane, a recovery compartment between the cathode and the cation selective membrane, and a water compartment between the anion selective membrane and the anode; (B) charging a solution of an ionic compound at a first concentration to the water compartment, and water to the recovery compartment; (C) charging a solution of the hydroxide compound at a second concentration to the feed compartment; (D) passing a current through the cell to produce the

Abstract: A process for the preparation of ascorbic acid starting from an ascorbate is characterized in that an ascorbate, e.g. sodium ascorbate, dissolved in water is decomposed under the influence of an electric field by means of ion-selective membranes into ascorbate ions and cations and the latter are separated spatially from one another and then, as a result of simultaneous generation of protons and hydroxide ions, the ascorbic acid is prepared from the liberated ascorbate ions and protons and, spatially separated therefrom, the corresponding hydroxide, e.g. sodium hydroxide, is also prepared from the cations and hydroxide ions.

Abstract: The present invention relates to methods and apparatus for reducing the fouling of ion-selective membranes used in the electrodialytic purification of organic acids. More particularly, the present invention relates to the use of nanofiltration and chelating agents for removal of impurities from an organic acid-containing feed material to reduce the fouling of ion-selective membranes used in electrodialysis.

Abstract: A process for the recovery of alkali metal hydroxide and acid from the alkali metal salts of monovalent anions which are mixed with the alkali metal salts of multivalent anions employs a water-splitting system composed of bipolar membranes in conjunction with ion-selective membranes; a two-compartment cell employs monovalent anion-selective membranes to define salt/base and acid compartments with the bipolar membranes, and a three-compartment cell employs, monovalent anion-selective and cation-selective membranes to define with the bipolar membranes, acid, salt and base compartments; the process has particular applicability to the conversion of the sodium/potassium chloride portion of the Electrostatic Precipitator (ESP) Catch of the recovery boiler of coastal and/or closed-cycle kraft pulp mills, a mixture of mostly sodium/potassium sulphate and chloride, into sodium/potassium hydroxide and hydrochloric acid; the remaining sodium/potassium sulphate solution, depleted in chloride, can thus be used as sodium/s