Abstract: An anode structure suitable for an electrochemical process is disclosed. The anode comprises a primary anode structure, also referred to as an anode frame, and a secondary metal substrate attached to the anode frame. The anode frame is a structural support and suitable electrical conductor. The metal substrate has an electrocatalytic coating and provides the anode with an anodic surface. The metal substrate is easily removable from the anode frame. Also disclosed is a method for refurbishing anodes according to the present invention. An anode comprising an anode frame and a metal substrate is refurbished by removing a depleted metal substrate from the frame and attaching a separate precoated metal substrate to the frame. The method of refurbishing optionally includes refurbishing the depleted metal substrate and using the refurbished substrate to refurbish the anode structure. A method for providing replacement anodes is also disclosed.

Abstract: A non-carbon metal-based anode of a cell for the electrowinning of aluminium comprising an electrically conductive metal substrate resistant to high temperature, the surface of which becomes passive and substantially inert to the electrolyte, and a coating adherent to the metal substrate making the surface of the anode electrochemically active for the oxidation of oxygen ions present at the electrolyte interface. The substrate metal may be selected from nickel, cobalt, chromium, molybdenum, tantalum and the Lanthanide series. The active constituents of the coating are for example oxides such as spinels or perovskites, oxyfluorides, phosphides or carbides, in particular ferrites. The active constituents may be coated onto the substrate from a slurry or suspension containing colloidal material and the electrochemically active material.

Abstract: An electrode with large active surface area is made by winding a Ti-fiber tow around a rectangular Ti-plate, and an electrocatalytic coating of three layers is applied. A precoat comprising a mixture of iridium dioxide and tantalum pentoxide is applied first, using a solution of the corresponding chloride salts in hydrochloric acid with some nitric acid added to inhibit corrosion of the metal. A sealing coat is then applied, comprising tin dioxide doped with antimony, in order to improve adhesion of the final oxide coat to the precoat. The third and final coat comprises particles of titanium dioxide doped with niobium in the +4 oxidation cemented with titanium dioxide that is doped with antimony. Anodes of this description are preferably assembled together with corrosion resistant cathodes in an alternating sequence, with a plastic coated fiber glass mesh placed between the anodes and cathodes to prevent short circuiting.

Abstract: The invention relates to a construction for ventilation of hydrogen gas comprising at least a first metallic layer (1), sensitive to hydrogen embrittlement, a second (2) metallic layer, and a mesh (4), wherein the first layer (1) is joined to the second layer (2), and said mesh (4), forming venting channels (5) through which channels (5) hydrogen can be vented, is joined to, and in between, said first (1) and second (2) metallic layers. The invention further concerns a method for production thereof.

Abstract: An electrode adapted for chromium plating from trivalent chromium baths which comprises a conductive base, an electrode material layer comprising iridium oxide formed thereon, and a porous layer formed on the surface of the electrode material layer. The porous can comprise an oxide containing at least one element selected from the group consisting of silicon, molybdenum, titanium, tantalum, zirconium, and tungsten. Use of this electrode for chromium plating reduces the oxidation of trivalent chromium into hexavalent chromium.

Abstract: A measuring method for determining the specific surface area available for reaction of a noble metal catalyst of an electrode for use in a polymer electrolyte membrane fuel cell. The method includes measuring the total specific surface area of the noble metal catalyst and the specific surface area of the noble metal catalyst mixed with a polymer electrolyte by detecting the adsorption amounts of carbon monoxide upon exposure to carbon monoxide after reduction in hydrogen, and subtracting the latter from the former. Also provided is an electrode material for use in a polymer electrolyte membrane fuel cell having excellent polarization characteristics by controlling the utilization of a noble metal catalyst determined from the total specific surface area and specific surface area available for reaction of the noble metal catalyst.

Abstract: A cathode for electrolysis comprising a hydrogen-occluding material for use in an electrolytic cell partitioned by the cathode into two chambers including a reaction chamber and an electrolysis chamber. The cell is arranged so that a reactant is reduced or hydrogenated in the reaction chamber. The cathode comprises an ion exchange membrane or porous membrane. A first layer made of a hydrogen-occluding metallic palladium or a palladium alloy is formed on the reaction chamber side of the membrane. A second layer which is a porous catalyst layer made of a platinum metal black or gold is formed on the first layer. Also disclosed is an electrolytic cell using the cathode for electrolysis.

Abstract: The present invention provides an improved anode formulation and an improved method of manufacture. More specifically, the invention provides a tri-layer anode having an improved service life when used, for example, for steel strip electrogalvinizing. In one embodiment of the invention, the anode is comprised of a titanium substrate which is roughened and heat treated and subsequently coated with a first coating of iridium oxide/tantalum oxide. After the anode is heat treated, it is next coated, preferably by an electrodeposition process with a second coating of platinum. Finally, the anode is coated with a third coating of iridium oxide/tantalum oxide and subsequently heat treated.

Abstract: Thin, light weight bipolar plates for use in electrochemical cells are rapidly, and inexpensively manufactured in mass production by die casting, stamping or other well known methods for fabricating magnesium or aluminum parts. The use of a light metal, such as magnesium or aluminum minimizes weight and simultaneously improves both electrical and thermal conductivity compared to conventional carbon parts. For service in electrochemical cells these components must be protected from corrosion. This is accomplished by plating the surface of the light weight metal parts with a layer of denser, but more noble metal. The protective metal layer is deposited in one of several ways. One of these is deposition from an aqueous solution by either electroless means, electrolytic means, or a combination of the two. Another is deposition by electrolytic means from a non-aqueous solution, such as a molten salt.