Abstract: Methods, systems, and techniques for desalinating monovalent anion species from wastewater. A system includes an electrodialysis stack that performs the desalination. The stack has a cathode, an anode, and at least one electrodialysis cell. The at least one electrodialysis cell includes a product chamber, a metal cation concentrating chamber adjacent to a cathodic side of the product chamber, and a transfer solution chamber adjacent to an anodic side of the product chamber. The product chamber and the metal cation concentrating chamber are each bounded by and share a cation exchange membrane, the product chamber and the transfer solution chamber are each bounded by and share a monovalent anion exchange membrane, and the transfer solution chamber is bounded on an anodic side by one of an anion exchange membrane and a monovalent anion exchange membrane. The wastewater may be generated by a flue gas desulfurization process.

Abstract: Processes, systems, and techniques for treating produced water drawn from a subterranean formation. The produced water is provided and contains dissolved solids and magnesium, calcium, and sodium ions. The produced water is desalinated using an electrically-driven membrane separation apparatus that includes alternating anion exchange membranes and cation exchange membranes defining opposing sides of alternating product and concentrate chambers. The desalinating involves flowing the produced water through the product chamber, flowing a second water through the concentrate chamber, and applying an electric potential across the cation and anion exchange membranes as the produced and second waters flow through the product and concentrate chambers, respectively. The product water is consequently produced and has a total dissolved solids content of between 300 mg/L and 8,000 mg/L, a total concentration of calcium ions and magnesium ions less than 100 mg/L, and a sodium adsorption ratio of 20 to 90.

Abstract: Methods, systems, and techniques for removing ammonium from ammonia-containing water involve using a stack that has alternating product chambers and concentrate chambers for receiving ammonia-containing water and an acidic solution, respectively, with the chambers being bounded by alternating cation exchange membranes and proton permselective cation exchange membranes. Ammonium moves from the product chambers to the concentrate chambers across the CEMs and protons move from the concentrate chambers to the product chambers across the pCEMs when the stack is in use. An electrolyzer may also be used to convert the ammonium in the concentrate chambers into nitrogen.

Abstract: Processes, systems, and techniques for multivalent ion desalination of a feed water use an apparatus that has a cathode, an anode, and an electrodialysis cell located between the cathode and anode. The cell has a product chamber through which the feed water flows, a multivalent cation concentrating chamber on a cathodic side of the product chamber through which the concentrated multivalent cation solution flows, and a multivalent anion concentrating chamber on an anodic side of the product chamber through which the concentrated multivalent anion solution flows. The product chamber and the multivalent cation concentrating chamber are each bounded by and share a cation exchange membrane, and the product chamber and the multivalent anion concentrating chamber are each bounded by and share an anion exchange membrane. A monovalent ion species is added to at least one of the concentrated multivalent cation solution and the concentrated multivalent anion solution.

Abstract: Methods, systems, and techniques for removing ammonium from ammonia-containing water involve using a stack that has alternating product chambers and concentrate chambers for receiving ammonia-containing water and an acidic solution, respectively, with the chambers being bounded by alternating cation exchange membranes and proton permselective cation exchange membranes. Ammonium moves from the product chambers to the concentrate chambers across the CEMs and protons move from the concentrate chambers to the product chambers across the pCEMs when the stack is in use. An electrolyzer may also be used to convert the ammonium in the concentrate chambers into nitrogen.

Abstract: Processes, systems, and techniques for multivalent ion desalination of a feed water use an apparatus that has a cathode, an anode, and an electrodialysis cell located between the cathode and anode. The cell has a product chamber through which the feed water flows, a multivalent cation concentrating chamber on a cathodic side of the product chamber through which the concentrated multivalent cation solution flows, and a multivalent anion concentrating chamber on an anodic side of the product chamber through which the concentrated multivalent anion solution flows. The product chamber and the multivalent cation concentrating chamber are each bounded by and share a cation exchange membrane, and the product chamber and the multivalent anion concentrating chamber are each bounded by and share an anion exchange membrane. A monovalent ion species is added to at least one of the concentrated multivalent cation solution and the concentrated multivalent anion solution.

Abstract: A process for preparing an acrylamide-based crosslinking monomer including reacting in the presence of a catalyst an isocyanate compound containing at least two isocyanate groups with one of acrylic acid and methacrylic acid.

Abstract: A resilient anion exchange membrane including a homogeneous cross-linked ion-transferring polymer substantially filling pores and substantially covering surfaces of a porous substrate, wherein the resilient anion exchange membrane is prepared by polymerizing a composition including a quaternary ammonium cationic surfactant monomer, a crosslinking monomer including two or more ethylenic groups, a free radical initiator, and a solvent.

Abstract: A process for preparing an acrylamide-based crosslinking monomer including reacting in the presence of a catalyst an isocyanate compound containing at least two isocyanate groups with one of acrylic acid and methacrylic acid.

Abstract: A process and system for removing ammonia from an aqueous ammonia solution. A first aqueous solution and the ammonia solution are flowed respectively through a first and a second separation chamber of a bipolar membrane electrodialysis (“BPMED”) stack. The first separation chamber is bounded on an anodic side by a cation exchange membrane and the second separation chamber is bounded on a cathodic side by the cation exchange membrane and on an anodic side by a bipolar membrane. The bipolar membrane has an anion-permeable layer and a cation-permeable layer respectively oriented to face the stack's anode and cathode. While the solutions are flowing through the stack a voltage is applied across the stack that causes the bipolar membrane to dissociate water into protons and hydroxide ions. The protons migrate into the second separation chamber and react there with ammonia to form ammonium ions that migrate to the first separation chamber.

Abstract: A process for preparing an acrylamide-based crosslinking monomer comprising reacting in the presence of a catalyst an isocyanate compound containing at least two isocyanate groups with one of acrylic acid or methacrylic acid. These acrylamide-based crosslinking monomers are used in the preparation of coating compositions, adhesive compositions curable by applying thermal or radiation energy, and in the preparation of cation or anion exchange membranes.

Abstract: A monovalent ion permselective ion exchange membrane comprising a base layer consisting of an ion exchange membrane, and a monovalent ion permselective layer affixed to the surface of the base layer. The monovalent ion permselective layer is formed by coating and polymerizing a polymerizable solution onto the base ion exchange membrane layer. The polymerizable solution comprises: (i) of an ionic monomer having one or more ethylenic groups selected from (meth)acryloxy groups, (meth)acryl-amido groups, and vinylbenzyl groups, (ii) a hydrophobic crosslinking monomer having two or more ethylenic groups selected from (meth)acryloxy groups, (meth)acrylamido groups, and vinylbenzyl groups, (iii) a free radical initiator, in (iv) a solvent medium. The monovalent ion permselective ion exchange membranes include monovalent cation permselective ion exchange membranes and monovalent anion permselective ion exchange membranes.

Abstract: A resilient anion exchange membrane including a homogeneous cross-linked ion-transferring polymer substantially filling pores and substantially covering surfaces of a porous substrate, wherein the resilient anion exchange membrane is prepared by polymerizing a composition including a quaternary ammonium cationic surfactant monomer, a crosslinking monomer including two or more ethylenic groups, a free radical initiator, and a solvent.

Abstract: A multivalent ion separating desalination system and associated process employs at least one multivalent ion separator subsystem to split sparingly soluble multivalent ion species from saltwater into highly soluble salts comprising multivalent cations and monovalent anions and salts comprising monovalent cations and multivalent anions.

Abstract: A method for making a resilient ion exchange membrane comprising polymerizing a composition containing at least an ionic surfactant monomer having an ethylenic group and a long hydrophobic alkyl group filling the pores of and covering the surfaces of a porous substrate. The hydrophobic long alkyl group in the ionic surfactant monomer provides ion exchange membranes with improved mechanical properties, and good chemical stability.

Abstract: A process for preparing an acrylamide-based crosslinking monomer comprising reacting in the presence of a catalyst an isocyanate compound containing at least two isocyanate groups with one of acrylic acid or methacrylic acid. These acrylamide-based crosslinking monomers are used in the preparation of coating compositions, adhesive compositions curable by applying thermal or radiation energy, and in the preparation of cation or anion exchange membranes.

Abstract: A method for making a resilient ion exchange membrane comprising polymerizing a composition containing at least an ionic surfactant monomer having an ethylenic group and a long hydrophobic alkyl group filling the pores of and covering the surfaces of a porous substrate. The hydrophobic long alkyl group in the ionic surfactant monomer provides ion exchange membranes with improved mechanical properties, and good chemical stability.

Abstract: A resilient cation exchange membrane including a porous matrix impregnated with a cross-linked homogenous ion-transferring polymer that fills the pores and substantially covers the surfaces of the porous matrix. The cross-linked homogenous ion-transferring polymer formed by polymerizing a homogeneous solution including (i) a hydrophilic ionic monomer selected from a group consisting of 2-acrylamido-2-methyl-1-propanesulfonic acid, 2-acrylamido-2-methyl-1-propanesulfonic acid salts, sodium 4-vinylbenzenesulfonate, and 3-sulfopropyl acrylate potassium, with (ii) a hydrophobic cross-linking oligomer selected from a group consisting of polyurethane oligomer diacrylate, polyester oligomer diacrylate, epoxy oligomer diacrylate, polybutadiene oligomer diacrylate, silicone diacrylate, dimethacrylate counterparts thereof, polyurethane oligomers having three or more vinyl groups, polyester oligomers having three or more vinyl groups, and mixtures thereof.

Abstract: A resilient anion exchange membrane including a porous matrix impregnated with a cross-linked homogenous ion-transferring polymer that fills the pores and substantially covers the surfaces of the porous matrix. The cross-linked homogenous ion-transferring polymer formed by polymerizing a homogeneous solution including (i) a hydrophilic ionic monomer selected from a group consisting of 3-methacryloylaminopropyl trimethylammonium chloride, vinylbenzyl trimethylammonium chloride, 3-acrylamidopropyl trimethylammonium chloride, 2-acryloyloxyethyl trimethylammonium chloride, and mixtures thereof, with (ii) a hydrophobic cross-linking oligomer selected from a group consisting of polyurethane oligomer diacrylate, polyester oligomer diacrylate, epoxy oligomer diacrylate, polybutadiene oligomer diacrylate, silicone diacrylate, dimethacrylate counterparts thereof, polyurethane oligomers having three or more vinyl groups, polyester oligomers having three or more vinyl groups, and mixtures thereof.

Abstract: A process for producing a resilient ion exchange membrane. The process comprises the steps of (1) selecting a porous matrix, (2) saturating the porous matrix with a homogenous solution comprising a mixture of: (i) a hydrophilic ionic monomer, (ii) a hydrophobic cross-linking oligomer and/or a comonomer, (iii) a free radical initiator, and (iii) a solvent for solubilizing the hydrophilic ionic monomer, the hydrophobic cross-linking oligomer and/or comonomer, and the free radical initiator into a homogenous mixture.