Abstract: A bipolar electrodialysis (BPED) cell is able to bipolar convert salt solutions into acid and base solutions. However, protons migrate through the anion exchange membranes and tend to neutralize the base solution. In a bipolar electrodialysis system described herein, multiple BPED cells are arranged to provide a multi-stage treatment system. Up to half, or up to one third, of the stages have cells with acid block anion membranes. The one or more stages with acid block anion membranes are located at the acid product output end of the system, where the acid concentration in the system is the highest. Replacing the traditional anion membranes in some of the stages with acid block anion membranes allows higher concentration products to be produced with moderate increase in energy consumption.

Abstract: A system of treating reject brine and capturing carbon dioxide (CO2) includes a two-stage electrodialysis (ED) process for producing multiple products with high purity from rejected brine and flue gas mixtures (10% CO2 and 90% N2) emitted from an industrial plant. According to an embodiment, the system includes a first electrodialysis (ED) stage and a second electrodialysis (ED) stage in series.

Abstract: A process for the preparation of butanediol includes providing an aqueous medium comprising magnesium succinate by fermentation of a carbohydrate source, in the presence of a magnesium base. The aqueous medium is processed wherein the magnesium succinate is treated with a monovalent base, prior to or after a crystallization step, to provide a magnesium base and an aqueous solution comprising a monovalent succinate salt. The concentration of the monovalent succinate salt is adusted to between 10 and 35 wt. %. The aqueous solution is subjected to water-splitting electrodialysis, to produce a first solution comprising monovalent base and a second solution comprising succinic acid and monovalent succinate salt, the electrodialysis causing conversion the monovalent succinate salt into succinic acid of 40 to 95 mole % calculated on a total molar amount of succinic acid and succinate present in solution. The second solution is separated into succinic acid and the monovalent succinate salt by crystallization.

Abstract: Process for the joint production of sodium carbonate and sodium bicarbonate out of sesquicarbonate, in which the sesquicarbonate is dissolved in water, in order to form a feed water solution comprising both sodium carbonate and sodium bicarbonate, in which at least part of the feed water solution is introduced into all the compartments of an electrodialyser and in which a sodium bicarbonate enriched solution and a sodium carbonate enriched solution are extracted from the compartments.

Abstract: The present invention provides a resin capable of contributing greatly to solve environmental problems and problems related to exhaustion of fossil fuel resources and having physical properties suited for practical use. The polyester according to the present invention has a diol and a dicarboxylic acid as constituent components and has an amount of terminal acid of 50 equivalents/metric ton or less.

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: A fluid treatment apparatus for treating a fluid comprises an electrochemical cell having fluid orifices to receive and release fluid, and a fluid passageway connecting the orifices with a water-splitting ion exchange membrane is exposed to the fluid in the passageway. First and second electrodes are positioned about the membrane. The apparatus also comprises a controller to control and operate a power supply and valve system. The power supply supplies a current to the first and second electrodes at sufficiently high current density to result in bacteriostasis, deactivation, or a reduction in the microorganisms in the fluid. The controller can also operate a set of cells to deionize fluid and regenerate the cells.

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: Buffer generators are described based on electrodialytic devices. The methods of using these devices can generate buffers for diverse applications, including separations, e.g., HPLC and ion chromatography. Also provided are chromatographic devices including the buffer generators, generally located upstream from a chromatography column, sample injector valve or both.

Abstract: The present invention provides a resin-wafer electrodeionization (RW-EDI) apparatus including cathode and anode electrodes separated by a plurality of porous solid ion exchange resin wafers, which when in use are filled with an aqueous fluid. The apparatus includes one or more wafers comprising a basic ion exchange medium, and preferably includes one or more wafers comprising an acidic ion exchange medium. The wafers are separated from one another by ion exchange membranes. The fluid within the acidic and/or basic ion exchange wafers preferably includes, or is in contact with, a carbonic anhydrase (CA) enzyme to facilitate conversion of bicarbonate ion to carbon dioxide within the acidic medium. A pH suitable for exchange of CO2 is electrochemically maintained within the basic and acidic ion exchange wafers by applying an electric potential across the cathode and anode.

Abstract: A process for the preparation of succinic acid comprising the steps of: a) providing an aqueous medium comprising magnesium succinate by fermentation of a carbohydrate source, in the presence of a magnesium base; b) processing the aqueous medium wherein the magnesium succinate is treated with a monovalent base, prior to or after a crystallisation step, to provide a magnesium base and an aqueous solution comprising a monovalent succinate salt; c) adjusting the concentration of the monovalent succinate salt to between 10 and 35 wt. %; d) subjecting the aqueous solution to water-splitting electrodialysis, to produce a first solution comprising monovalent base and a second solution comprising succinic acid and monovalent succinate salt, the electrodialysis causing conversion of 40 to 95 mole %; e) separating the second solution into succinic acid and the monovalent succinate salt by crystallisation; f) recycling the monovalent succinate salt solution of step e) to step d).

Abstract: A cartridge for an ion exchanging electrochemical cell, the cartridge comprising at least one spiral wound, textured, bipolar ion exchange membrane having (i) an anion exchange layer abutting a cation exchange layer with continuous contact between the anion exchange layer and the cation exchange layer; and (ii) an exposed textured surface having a pattern of texture features. A method of manufacturing a cartridge for an ion exchange electrochemical cell comprises winding the textured, bipolar ion exchange membrane into a spiral wound membrane.

Abstract: A textured water-splitting membrane comprises an anion exchange layer abutting a cation exchange layer to form a heterogeneous water-splitting interface therebetween, and a textured surface having a pattern of texture features comprising spaced apart peaks and valleys. The membranes can also have an integral spacer on the membrane. A cartridge can be fabricated with a plurality of the membranes for use in an electrochemical cell. The electrochemical cell can be part of an electrochemical ion exchange system.

Abstract: An electrochemical cell having two or more diffusion bonded layers, which demonstrates a high degree of ruggedness, reliability, efficiency and attitude insensitiveness, is provided. The novel cell structure simplifies construction and operation of these cells. Also provided is a method for passive water removal from these cells. The inventive cell, as well as stacks made using these cells, is suitable for use in applications such as commercial space power systems, long endurance aircraft, undersea power systems, remote backup power systems, and regenerative fuel cells.

Abstract: An electrochemical cell 102 comprises an ion exchange membrane 10 having anion and cation exchange materials. The membrane 10 can have separate anion and cation exchange layers 12, 14 that define a heterogeneous water-splitting interface therebetween. In one version, the membrane 10 has a textured surface having a pattern of texture features 26 comprising spaced apart peaks 28 and valleys 30. The membranes 10 can also have an integral spacer 80. A cartridge 100 can be fabricated with a plurality of the membranes 10 for insertion in a housing 129 of the electrochemical cell 102. The housing 129 can also have a detachable lid 96 that fits on the cartridge 100. The electrochemical cell 102 can be part of an ion controlling apparatus 120.

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: An electrodialysis cell is operated in the presence of organic compounds that binds or chelates with the multivalent metals to form a metal chelating buffer. Among other things, this binding or chelating reduces power consumption, produces a stable cell operation, and avoids a fouling of the membranes while significantly improving membrane life, reliability, and operating costs. When a chelating agent is added to a salt solution containing multivalent cations, the chelating agent strongly binds with the cations, forming large size complexes. An ion exchange membrane retains these complexes within the compartment of the electrodialysis cell containing the feed solution. The multivalent cations is greatly inhibited from being transported across the cation exchange membrane, thus reducing the fouling of the cation membranes. Concurrently, the precipitation of the metals transported to the base loop is substantially abated.

Abstract: The present invention relates to an electrochemical process for producing ionic liquids. The ionic liquids may be hydrophilic or hydrophobic ionic liquids. The ionic liquids are made by subjecting an electrochemical cell to electrolysis.

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: An electrodialysis cell is operated in the presence of organic compounds that bind or chelate with the multivalent metals to form metal-chelate buffers. Among other things, this binding or chelating reduces power consumption, produces a stable cell operation, and avoids a fouling of the membranes while significantly improving membrane life, reliability, and operating costs. When a chelating agent is added to a salt solution containing multivalent cations, the chelating agent strongly binds with the cations, forming large size complexes. An ion exchange membrane retains these complexes within the compartment of the electrodialysis cell containing the feed solution. The multivalent cations is greatly inhibited from being transported across the cation exchange membrane, thus reducing the fouling of the cation membranes. Concurrently, the precipitation of the metals in the base loop is substantially abated.

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: The present invention relates to a process for separating organic acids from aqueous solutions by the use of electrochemical processes such as electrolysis and electrodialysis. These processes can be used, for example, to purify aqueous solutions produced in aldol condensation processes.

Abstract: A bipolar membrane, usable for electrodialysis of aqueous electrolytes, comprises two ion exchange membranes, respectively anionic and cationic, juxtaposed along a common surface, wherein, along said common surface, a gel based on hydrated metal sulpate and/or sulphite, including less than 0.01 mol % of indium, cerium, manganese and copper sulphates gel, is formed.

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: The present invention relates to electrochemical methods for the recovery of ascorbic acid from an ascorbate salt without the co-generation of a waste salt stream and while maintaining high conductivity of the electrochemical cell thereby providing for quantitative conversion of the salts to ascorbic in both batch and continuous mode processes. In one embodiment the feed stream comprising an ascorbate salt is dissociated under the influence of an electric field and subjected to water splitting electrodialysis. The ascorbate ion combines with a proton and the salt cation combines with a hydroxyl ion to form ascorbic acid and base, respectively. The feed stream further comprises an inorganic salt which maintains high conductivity in the cell, facilitates quantitative conversion of ascorbate salts to ascorbic acid in both batch and continuous mode processes, and promotes precipitation and crystallization of ascorbic acid as a fine powder.

Abstract: Process for manufacturing sodium hydroxide by the electrodialysis of sodium carbonate in an electrodialysis cell having three compartments, in which an aqueous sodium carbonate solution is introduced into a compartment of the cell which is bounded between two cationic membranes, an acid is introduced into a compartment which is bounded between one of the cationic membranes and a cationic face of a bipolar membrane, and an aqueous sodium hydroxide solution is removed from a compartment which is adjacent to an anionic face of the bipolar membrane.

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 electrochemical cell for removing ions from a solution stream comprises a housing having first and second electrodes. At least one water-splitting ion exchange membrane is positioned between the electrodes, the water-splitting membrane comprising (i) a cation exchange surface facing the first electrode, and (ii) an anion exchange surface facing the second electrode. A solution stream pathway is defined by the water-splitting membrane. The solution stream pathway comprises (i) an inlet for influent solution stream, (ii) at least one channel that allows influent solution stream to flow past at least one surface of the water-splitting membrane to form one or more treated solution streams, and (iii) a single outlet that combines the treated solution streams to form a single effluent solution.

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 method for recovering salt from a process stream containing organic contaminants is provided, comprising directing the waste stream to a desalting electrodialysis unit so as to create a concentrated and purified salt permeate and an organic contaminants containing stream, and contacting said concentrated salt permeate to a water-splitting electrodialysis unit so as to convert the salt to its corresponding base and acid.

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