Abstract: This specification describes an ion exchange membrane and a method of making it. The membrane may be used, for example, in an electrodialysis module or electrochemical cell. The membrane comprises an ion exchange polymer and inorganic particles preferably linked to the ion exchange polymer. To make a membrane, inorganic particles are mixed into an ion exchange membrane pre-cursor. A polymerization initiator or catalyst is then added and the resulting mixture is placed in a form and cured. The inorganic particles may comprise, for example, an oxidized form of graphite such as graphite oxide. The ion exchange polymer may comprise an ionic monomer, containing a quaternary ammonium group for anion exchange or a sulfonate group for cation exchange, along with a crosslinking co-monomer containing polymerizable diacrylic functionalities. The membrane is self-supporting and can be made without a supporting fabric.

Abstract: An ion exchange membrane and a method of making it. The membrane may be used, for example, in an electrodialysis module or electrochemical cell. The membrane comprises an ion exchange polymer and inorganic particles preferably linked to the ion exchange polymer. To make a membrane, inorganic particles are mixed into an ion exchange membrane pre-cursor. A polymerization initiator or catalyst is then added and the resulting mixture is placed in a form and cured. The inorganic particles may comprise, for example, an oxidized form of graphite such as graphite oxide. The ion exchange polymer may comprise an ionic monomer, containing a quaternary ammonium group for anion exchange or a sulfonate group for cation exchange, along with a crosslinking co-monomer containing polymerizable diacrylic functionalities. The membrane is self-supporting and can be made without a supporting fabric.

Abstract: An ion exchange membrane and a method of making it. The membrane may be used, for example, in an electrodialysis module or electrochemical cell. The membrane comprises an ion exchange polymer and inorganic particles preferably linked to the ion exchange polymer. To make a membrane, inorganic particles are mixed into an ion exchange membrane pre-cursor. A polymerization initiator or catalyst is then added and the resulting mixture is placed in a form and cured. The inorganic particles may comprise, for example, an oxidized form of graphite such as graphite oxide. The ion exchange polymer may comprise an ionic monomer, containing a quaternary ammonium group for anion exchange or a sulfonate group for cation exchange, along with a crosslinking co-monomer containing polymerizable diacrylic functionalities. The membrane is self-supporting and can be made without a supporting fabric.

Abstract: Acid block anionic selective polymeric membranes are provided of the type having a woven or non-woven cloth reinforcing structure. The polymer of the membrane is prepared by the process comprising copolymerizing components I, II, and III wherein I is an ethylenically unsaturated aliphatic or aromatic tertiary or quaternary amine monomer. II is a cross-linking monomer, and III is vinylbenzyl chloride. The reaction is conducted in the presence of a free radical polymerization initiator. Additionally, anionic exchange membranes of the type used in electrodialysis apparatus are disclosed and comprise a woven or nonwoven cloth that is impregnated with a copolymer comprising the reaction products of components I, II, and III.

Abstract: Acid block anionic selective polymeric membranes are provided of the type having a woven or non-woven cloth reinforcing structure. The polymer of the membrane is prepared by the process comprising copolymerizing components I, II, and III wherein I is an ethylenically unsaturated aliphatic or aromatic tertiary or quaternary amine monomer. II is a cross-linking monomer, and III is vinylbenzyl chloride. The reaction is conducted in the presence of a free radical polymerization initiator. Additionally, anionic exchange membranes of the type used in electrodialysis apparatus are disclosed and comprise a woven or nonwoven cloth that is impregnated with a copolymer comprising the reaction products of components I, II, and III.

Abstract: A fluid from a fermentation process or the like is passed or circulated through chambers of a bipolar membrane electrodialysis unit to separate an ionizable organic acid stream and at least one co-ion or residual stream. The organic acid stream is preferably concentrated (e.g., by recirculation, dewatering or both), and a product is recovered from the concentrated stream, for example by crystallization, and other outputs from the electrodialysis unit may be integrated with overall treatment and applied elsewhere in the treatment system. Depleted feed may be returned upstream to enhance yield, condition the medium or form a by-product. Treatment systems of the invention may replace a cation exchange bed and/or various filter arrangements, and recirculation of the feed and product flows through the unit enhance recovery, separation and quality of the target species.

Abstract: A sheet having anion exchange functionality and a sheet having cation exchange functionality are juxtaposed and joined by current bonding into a unitary bipolar membrane. This may be done without added reactants or bonding agents by placing the two-layer assembly between opposed electrodes in a fluid cell, preferably at pressure, and applying power across the cell to split water in a junction region of the membrane assembly. Preferably the anion exchange sheet is treated with an iron salt solution so as to incorporate or immobilize the metal in the polymer during the current bonding process, and enhance operating characteristics of the bipolar junction. Membrane peel strength is comparable to or greater than that of an underlying sheet of ion exchange material, but the bonding is fully reversible, e.g., by soaking in a concentrated solution. Preferably both sheets include an aromatic backbone or cross-linker component.

Abstract: A fluid from a fermentation process or the like is passed or circulated through chambers of a bipolar membrane electrodialysis unit to separate an ionizable organic acid stream and at least one co-ion or residual stream. The organic acid stream is preferably concentrated (e.g., by recirculation, dewatering or both), and a product is recovered from the concentrated stream, for example by crystallization, and other outputs from the electrodialysis unit may be integrated with overall treatment and applied elsewhere in the treatment system. Depleted feed may be returned upstream to enhance yield, condition the medium or form a by-product. Treatment systems of the invention may replace a cation exchange bed and/or various filter arrangements, and recirculation of the feed and product flows through the unit enhance recovery, separation and quality of the target species.

Abstract: Novel styrene sulfonate-based polymers and cation exchange membranes which are particularly suitable for use in electrodialysis of whey and improved methods for electrodialysis of whey are disclosed.

Abstract: Novel styrene sulfonate-based polymers and cation exchange membranes which are particularly suitable for use in electrodialysis of whey and improved methods for electrodialysis of whey are disclosed.

Abstract: Novel styrene sulfonate-based polymers and cation exchange membranes which are particularly suitable for use in electrodialysis of whey and improved methods for electrodialysis of whey are disclosed.