Abstract: A grid anode for cathodic protection of steel reinforced concrete structures formed of multiple valve metal strips including multiple electric current-carrying valve metal strips. Valve metal strip grid anodes without an electrocatalytic metal surface can be used in a cathodic protection system operated at an anode current density up to about 20 milliamps per square foot. Composite anodes having an electrocatalytic metal coating are useful at higher anode current densities.

Abstract: A metal anode useful in a galvanic or impressed current cathodic protection system for a steel reinforced concrete article is a unitary, multi-plane, porous, metal anode strip or ribbon having a plurality of louvers defining a plane or planes at the lateral extremities of said louvers. In one embodiment, louvers extending in their long dimension longitudinally on the anode strip are spaced apart from adjacent louver units by an intermediate plane. Louvered anode strips consisting of a valve metal or alloy or mixture thereof are useful at an anode current density of up to about 20 milliamps per square foot. Louvered metal anodes comprising an electrocatalytically active coating on a valve metal substrate are useful at higher anode current densities. Sacrificial metal anodes such as zinc anodes are useful in galvanic cathodic protection systems.

Abstract: A flexible, nonstretchable, titanium, ladder anode for cathodic protection of steel reinforced concrete structures formed of multiple titanium strips including multiple electric current-carrying titanium strips. Ladder anodes of titanium without an electrocatalytically active metal coating can be used in a cathodic protection system operated at an anode current density up to about 20 milliamps per square foot. Ladder anodes of titanium having an electrocatalytically active metal coating are additionally useful at higher anode current densities. The ladder anodes form at the intersections of the strips less than 200 nodes per square meter and have a surface area of about 500 to about 900 square inches per pound.

Abstract: Method for the regeneration of active carbon and polymeric adsorbents having oxidizable, organic pollutants adsorbed thereon by electrochemical and chemical means and apparatus therefor. The method involves a desorption step and a decomposition step. Desorption is accomplished in one embodiment by flowing an aqueous stream at a preselected pH through the adsorbent material. Generally, decomposition is accomplished by contacting an aqueous stream containing an organic pollutant with hydroxyl radicals. Sequential or simultaneous desorption and decomposition can also take place during electrolysis in an electrolytic cell. During decomposition the active carbon can be made a carbon bed electrode of the cell. Electrolysis to produce peroxide can take place in the presence of a transition metal or a chelate of a transition metal while feeding an oxygen containing gas to the electrolysis cell.

Abstract: Method for the regeneration of active carbon having oxidizable, organic pollutants adsorbed thereon by electrochemical and chemical means and apparatus therefor. The method involves a desorption step prior to a decomposition step. Each step involves conducting electrolysis in a cell using the active carbon as a carbon bed electrode. It is advantageous to conduct the electrolysis in the presence of a transition metal or a chelate of a transition metal while feeding an oxygen containing gas to the electrolysis cell.

Abstract: An electrolytic cell and process for the cogeneration of a peroxy acid and salts thereof in an anolyte compartment of the cell and hydrogen peroxide at a desired ratio of an alkali metal hydroxide to hydrogen peroxide in the catholyte compartment of the cell. An ammonium compound is present as a reactant in the catholyte compartment. Ammonia is recycled from the catholyte compartment of the cell to the anolyte compartment of the cell or removed as a product.

Abstract: A continuous length anode is formed of relatively small valve metal wire having a electrocatalytic coating braided into a highly flexible ribbon. The wire may be copper cored. The valve metal is preferably titanium, although tantalum or niobium are also preferred. The coating is preferably a mixed metal oxide coating. The braid is formed from wire sizes of from about 1/16 or less to about 1/8" in diameter and the braided ribbon may be about 0.1 to about 6" inches wide. Four system applications are disclosed, two for steel reinforced concrete, one for a tank bottom, and one for a buried pipe. The braided anode may be used in combination with valve metal ribbon or bar and may readily be electrically connected to power feeds or to itself by spot weld or crimp connections. Power feeds may be connected at a butt end or anywhere along the length of the braid.

Abstract: An electrode base comprising a valve metal core provided with an ultimately protective, barrier precursor forming coating which is dried at relatively low temperature; e.g. room temperature to 280.degree. C. prior to application of an electrocatalytic precursor forming coating thereon. The step of pre-formation of a barrier layer is eliminated.

Abstract: A porous diaphragm is disclosed for use in an electrochemical cell having at least one electrode characterized as porous and self-draining. The diaphragm provides a way of obtaining uniformity of flow of an electrolyte through the diaphragm even when exposed to varying electrolyte head pressures. The porous diaphragm of the invention has a plurality of layers of a microporous polyolefin film or a composite comprising the microporous polyolefin film and a support fabric resistant to deterioration upon exposure to an aqueous solution of an ionizable compound.

Abstract: A porous diaphragm is disclosed for use in an electrochemical cell having at least one electrode characterized as porous and self-draining. The diaphragm provides a uniformity of flow of an electrolyte through the diaphragm even when exposed to varying electrolyte head pressures. The porous diaphragm of the invention has a plurality of layers of a microporous polyolefin film or a composite comprising the microporous polyolefin film and a support fabric resistant to deterioration upon exposure to an aqueous solution of an ionizable compound.

Abstract: Cell having a porous, self-draining, gas diffusion electrode contained within a frame and having on both sides of said electrode a liquid permeable microporous diaphragm. The electrode assembly contains an internally positioned current distributor. The cell has two oppositely charged electrodes separated by the electrode assembly which divides a single electrolyte compartment. In operation, electrolyte is flowed into the electrolyte compartment and spent electrolyte is removed. In one embodiment of the invention, the electrolyte is internally circulated by turbulent flow of electrolyte as the result of the upward movement of gas released at an electrode.