Abstract: Electrocatalytic generation of halogenated biocides are disclosed by electrolyzing low salinity water with an applied current. The direction of the applied current is reversed periodically, for a shorter duration, and at a lower current density. Mixed types of electrodes are utilized without a significant reduction in reliability and performance.

Abstract: The invention provides low cost methods and apparatus that utilize at least one carbon-filled polymeric electrode to electrolytically generate desirable products.

Abstract: The present invention pertains to electrolytic diaphragm cells, particularly for the electrolysis of brine to produce chlorine and caustic. The innovation resides generally in the discovery that electrolytic cell operation can be desirably enhanced by compressing the diaphragm between anode and cathode. This compression of the diaphragm reduces the diaphragm thickness from an original thickness, e.g., from an original thickness of a diaphragm freshly deposited on a cathode. The reduced thickness of the diaphragm provides for cell operation that is less than zero gap operation. By maintaining the diaphragm under compression and in a reduced thickness, the cell operates with a narrower interelectrode gap and consequently at a desirably reduced cell voltage.

Abstract: A compound electrode incorporating a lead substrate utilizes the lead as a support structure. This support structure provides a surface that engages a valve metal expanded metal mesh. The mesh member has a front and back surface with the back surface facing the lead support structure. At least the front surface of the mesh member is an active surface. Securing of the mesh member to the lead support structure in electrical connection permits the lead support structure to serve as a current distributor for the mesh member. The mesh member may engage the surface of the lead support structure by pressing or rolling the mesh onto the lead. Other engagement means can include the use of fasteners, or welding and the like. The resulting structure can be particularly useful as an electrode assembly for use in an electrolytic cell that serves for the electrowinning of a metal.

Abstract: A compound electrode incorporating a lead substrate utilizes the lead as a support structure. This support structure provides a surface that engages a mesh member, e.g., a valve metal expanded metal mesh. The mesh member has a front and back surface with the back surface facing the lead support structure. At least the front surface of the mesh member is an active surface. Securing of the mesh member to the lead support structure in electrical connection permits the lead support structure to serve as a current distributor for the mesh member. The mesh member may engage the surface of the lead support structure as by pressing or rolling the mesh onto the lead. Other engagement means can include the use of fasteners, or welding and the like. The resulting structure can be particularly useful as an electrode assembly for use in an electrolytic cell that serves for the electrowinning of a metal.

Abstract: A method of protecting reinforced concrete structures comprising of applying a protective cathodic coating containing a non-corroding metal and an electrochemically active material on concrete wherein the protective coating is formed by thermally spraying a mixture of said non-corroding metal such as a valve metal and said electrochemically active material. The coating may also be formed by applying a precursor of the electrochemically active material and a metal-containing layer to concrete, then anodically polarizing said metal layer to convert the precursor into an electrochemically active material.

Abstract: A metal coating of typically a valve metal, especially a titanium metal coating, is applied by thermal spraying to the surface of concrete, most particularly steel-reinforced concrete. The metal such as titanium may be sprayed by any one of several thermal spraying techniques including flame spray, electric-arc spray, plasma spray, high-velocity oxyfuel spray, or detonation gun spray. The metal coating should be tightly adhered to the concrete and desirably will have a porosity to facilitate extensive coating of the metal itself, as well as facilitate any activation that may be needed for the metal. Such activation can be in the form of an electrochemically active material which allows the coating to function in electrochemically active form. One coating option is to apply a solution onto the spray-applied metal, then polarize the metal anodically to effect deposition of active material on the metal.

Abstract: Cathodic protection of a reinforced concrete structure utilizes a metal anode such as a zinc anode in combination with a pressure sensitive ionically conductive hydrogel in contact with at least a portion of the surface of the anode. Preferably, the anode and ionically conductive hydrogel are flexible and supplied in roll form. The combination may further include the addition of salt to the hydrogel as well as application to the metal-hydrogel combination of Type III cement. The cathodic protection may be carried out with or without a power source.

Abstract: A catalytically-coated valve metal reference electrode is used to measure the potential of reinforcing members in concrete in a system to cathodically protect the same.