Abstract: A flow battery having at least one rechargeable cell is disclosed. The at least one rechargeable cell can include an anolyte compartment, a catholyte compartment, and an anion exchange membrane positioned between the anolyte and catholyte compartments. The anion exchange membrane can have a thickness of less than 100 ?m and a steady state diffusivity of less than 0.4 ppm/hr/cm2 with respect to a cation species in an electrolyte of the rechargeable cell. A method of facilitating use of a flow battery including providing the anion exchange membrane is also disclosed. A method of facilitating storage of an electric charge comprising providing the flow battery is also disclosed. A method of producing an anion exchange membrane is also disclosed.

Abstract: An electrochemical separation device includes a first electrode, a second electrode, and a cell stack including a plurality of sub-blocks each having alternating depleting compartments and concentrating compartments and each including frame and channel portions disposed between the first electrode and the second electrode. An internal seal formed of a first material is disposed between and in contact with the channel portions between adjacent sub-blocks in the cell stack and configured to prevent leakage between depleting compartments and concentrating compartments in the adjacent sub-blocks. An external seal formed of a second material having at least one material parameter different from the first material is disposed between and in contact with the frames of the adjacent sub-blocks in the cell stack and configured to prevent leakage from an internal volume of the electrochemical separation device to outside of the electrochemical separation device.

Abstract: A method of operating an electrochemical cell including introducing an aqueous solution into the electrochemical cell, applying a current across an anode and a cathode to produce a product, monitoring the voltage, dissolved hydrogen, or a condition of the aqueous solution, and applying the current in a pulsed waveform responsive to one of the measured parameters is disclosed. An electrochemical system including an electrochemical cell including an anode and a cathode, a source of an aqueous solution having an outlet fluidly connectable to the electrochemical cell, a sensor for measuring a parameter, and a controller configured to cause the anode and the cathode to apply the current in a pulsed waveform responsive to the parameter measurement is disclosed. Methods of suppressing accumulation of hydrogen gas within the electrochemical cell are also disclosed. Methods of facilitating operation of an electrochemical cell are also disclosed.

Abstract: An electrochemical cell including a first chamber having an anode, a second chamber having a cathode, at least one ionic connection between the first chamber and the second chamber, such that liquid electrolyte from the first chamber is prevented from mixing with liquid electrolyte in the second chamber is provided. The first chamber and the second chamber can be arranged in parallel and positioned remotely from each other. An electrochemical system including the electrochemical cell, and first and second sources of saline aqueous solutions is also provided. Water treatment systems are also provided. A method of operating an electrochemical cell including introducing first and second saline aqueous solutions into first and second chambers of the electrochemical cell, and applying a current across the anode and the cathode to generate first and second products, respectively is also provided. A method of facilitating operation of an electrochemical cell is also provided.

Abstract: Methods of treating water having organic contaminants are disclosed. The methods include performing a first treatment on the water effective to oxidize a predetermined amount of the organic contaminant and electrochemically treating the water. The methods include introducing a hydrogen peroxide (H2O2) containing reagent into the water, allowing the H2O2 containing reagent to react with the organic contaminant for a reaction time effective to oxidize a predetermined amount of the organic contaminant, and electrochemically treating the water. Systems for treating water are also disclosed. The systems include an electrochemical cell, a source of an H2O2 containing reagent upstream from the electrochemical cell, and a controller operable to regulate a reaction time of the H2O2 containing reagent in the water and a potential applied to the electrochemical cell.

Abstract: An electrochlorination process includes treating water from a source of water in an advanced water conditioning system that removes at least a portion of anions and cations from the water and produces demineralized water, blending the demineralized water with sodium chloride to form a brine solution, and treating the brine solution in an electrolyzer to form a disinfection solution including sodium hypochlorite having a concentration of chlorate of less than 0.25 mg/L.

Abstract: Electrochemical treatment for the removal of poly- and perfluorolkyl substances from water is disclosed. An electrochemical cell may include a Magnéli phase titanium oxide electrode.

Abstract: An electrochemical separation device includes a first electrode, a second electrode, a cell stack including alternating depleting compartments and concentrating compartments disposed between the first electrode and the second electrode, an inlet manifold configured to introduce a fluid to one of the depleting compartments or the concentrating compartments an outlet manifold, and one or more of a fluid flow director disposed within the inlet manifold and having a surface configured to alter a flow path of the fluid introduced into the inlet manifold and direct the fluid into the one of the depleting compartments or the concentrating compartments, and a second fluid flow director disposed within the outlet manifold and having a surface configured to alter a flow path of the fluid introduced into the outlet manifold via one of the depleting compartments or the concentrating compartments.

Abstract: An electrochemical separation device includes a first electrode, a second electrode, and a cell stack including a plurality of sub-blocks each having alternating depleting compartments and concentrating compartments and each including frame and channel portions disposed between the first electrode and the second electrode. An internal seal formed of a first material is disposed between and in contact with the channel portions between adjacent sub-blocks in the cell stack and configured to prevent leakage between depleting compartments and concentrating compartments in the adjacent sub-blocks. An external seal formed of a second material having at least one material parameter different from the first material is disposed between and in contact with the frames of the adjacent sub-blocks in the cell stack and configured to prevent leakage from an internal volume of the electrochemical separation device to outside of the electrochemical separation device.

Abstract: Methods for treating phosphogypsum-containing water are disclosed. The water may be treated so as to promote precipitation of one or more target constituents and to facilitate downstream membrane treatment. A coagulant may be added to promote phosphate recovery. Ammonia may optionally be removed. Related systems are also disclosed.

Abstract: Methods of treating a waste stream containing perfluoroalkyl substances (PFAS) are disclosed. The methods include directing the waste stream to a dilution compartment of an electrochemical separation device, directing a treatment stream to a concentration compartment of the electrochemical separation device, and applying a voltage across the electrodes to produce a dilute stream substantially free of the PFAS and a concentrate stream. At least one of the waste stream and the treatment stream comprises a water miscible organic solvent. Methods of concentrating PFAS from a wastewater are also disclosed. PFAS concentration systems are also disclosed. The systems include a column comprising an ion exchange resin and an electrochemical separation device having a dilution compartment fluidly connected to an outlet of the column. Methods of facilitating treatment of a waste stream containing PFAS are also disclosed.

Abstract: A system for treating a source of water contaminated with PFAS is disclosed. The system includes a PFAS separation stage having an inlet fluidly connectable to the source of water contaminated with PFAS, a diluate outlet, and a concentrate outlet and a PFAS elimination stage positioned downstream of the PFAS separation stage and having an inlet fluidly connected to an outlet of the PFAS separation stage, the elimination of the PFAS occurring onsite with respect to the source of water contaminated with PFAS, with the system maintaining an elimination rate of PFAS greater than about 99%. A method of treating water contaminated with PFAS is also disclosed.

Abstract: An electrochemical separation device includes a first electrode, a second electrode, a cell stack including alternating depleting compartments and concentrating compartments disposed between the first electrode and the second electrode, an inlet manifold configured to introduce a fluid to one of the depleting compartments or the concentrating compartments an outlet manifold, and one or more of a fluid flow director disposed within the inlet manifold and having a surface configured to alter a flow path of the fluid introduced into the inlet manifold and direct the fluid into the one of the depleting compartments or the concentrating compartments, and a second fluid flow director disposed within the outlet manifold and having a surface configured to alter a flow path of the fluid introduced into the outlet manifold via one of the depleting compartments or the concentrating compartments.

Abstract: An electrochlorination system includes an electrolyzer fluidically connectable between a source of feed fluid and a product fluid outlet, and a sub-system configured to one of increase a pH of the feed fluid, or increase a ratio of monovalent to divalent ions in the feed fluid, upstream of the electrolyzer.

Abstract: Methods for treating phosphogypsum-containing water are disclosed. The water may be treated so as to promote precipitation of one or more target constituents and to facilitate downstream membrane treatment. A coagulant may be added to promote phosphate recovery. Related systems are also disclosed.

Abstract: A wastewater treatment system comprises an actinic radiation reactor and a concentric tube electrode electrochemical cell in fluid communication between a source of electrolyte and the actinic radiation reactor. The electrochemical cell is configured to produce a chlorinated effluent including sodium hypochlorite. A conduit fluidically couples an outlet of the electrochemical cell to an inlet of the actinic radiation reactor and is configured to deliver the chlorinated effluent into the actinic radiation reactor.

Abstract: An electrochemical cell includes a housing having an inlet, an outlet, and a central axis and an anode-cathode pair disposed concentrically within the housing about the central axis and defining an active area between an anode and a cathode of the anode-cathode pair. An active surface area of at least one of the anode and the cathode has a surface area greater than a surface area of an internal surface of the housing. The anode-cathode pair is configured and arranged to direct all fluid passing through the electrochemical cell axially through the active area.

Abstract: A monovalent selective ion exchange membrane is disclosed. The membrane includes a polymeric microporous substrate, a cross-linked ion-transferring polymeric layer on a surface of the substrate, and a charged functionalizing layer covalently bound to the ion-transferring layer by an acrylic group. A method of producing a monovalent selective cation exchange membrane is also disclosed. The method may include chemically adsorbing an acrylic intermediate layer comprising a chlorosulfonated methacrylate group to a cross-linked ion-transferring polymeric layer on a surface of a polymeric microporous substrate, aminating the chlorosulfonated methacrylate group to attach an amine group layer, and functionalizing the amine group layer with a charged compound layer to produce the cation exchange membrane.

Abstract: Methods of producing an ion exchange membrane support are disclosed. The methods include saturating a polymeric microporous substrate with a charged monomer solution comprising at least one functional monomer, a cross-linking agent, and an effective amount of at least one photopolymerization initiator and polymerizing the at least one functional monomer by exposing the saturated polymeric microporous substrate to ultraviolet light under conditions effective to cross-link the at least one functional monomer and produce the ion exchange membrane support. Methods of producing a monovalent selective ion exchange membrane are also disclosed. The methods include functionalizing an exterior surface of the ion exchange membrane support with a charged compound layer, drying the ion exchange membrane support and soaking the ion exchange membrane support in a solution comprising an acid or a base for an amount of time effective to produce the monovalent selective ion exchange membrane.

Abstract: An electrochemical cell including a first chamber having an anode, a second chamber having a cathode, at least one ionic connection between the first chamber and the second chamber, such that liquid electrolyte from the first chamber is prevented from mixing with liquid electrolyte in the second chamber is provided. The first chamber and the second chamber can be arranged in parallel and positioned remotely from each other. An electrochemical system including the electrochemical cell, and first and second sources of saline aqueous solutions is also provided. Water treatment systems are also provided. A method of operating an electrochemical cell including introducing first and second saline aqueous solutions into first and second chambers of the electrochemical cell, and applying a current across the anode and the cathode to generate first and second products, respectively is also provided. A method of facilitating operation of an electrochemical cell is also provided.