Abstract:
An apertured and porous metal article (1) can find use, for example, in diaphragm or membrane electrolysis cells. The article (1) may comprise a thin and flexible metal foam of small pores (2) which, typically, has been perforated with large apertures (3). The article (1) may also be provided with an electrocatalytic coating. It can be in substantial physical contact with a membrane or diaphragm separator (12) used in the cell for separating anode and cathode members or compartments. There is also disclosed the preparation of the article (1) and an electrolysis cell utilizing the resulting apertured and porous metal article (1).
Abstract:
An aluminum production cell with a non-conductive cell bottom composed predominantly of alumina (1) has a plurality of vertical current collector plates or posts (3), e.g., of steel protected at their upper ends by a carbon body (4), e.g., a plate, slab or cap which contacts the cathodic pool of molten aluminum (10).
Abstract:
A method of electrowinning a metal by electrolysis of a melt containing a dissolved species of the metal to be won using a non-consumable anode having a metal, alloy or cermet substrate and an operative anode surface which is a protective surface coating of cerium oxyfluoride preserved by maintaining in the melt a suitable concentration of cerium, is characterized by using an anode provided with an electronically conductive oxygen barrier on the surface of the metal, alloy or cermet substrate. The barrier layer may be a chromium oxide film on a chromium-containing alloy substrate. Preferably the barrier layer carries a ceramic oxide layer, e.g. of stabilized copper oxide which acts as anchorage for the cerium oxyfluoride.
Abstract:
A copper metal foam, or a large pore size metal foam, particularly a large pore size nickel metal foam, is utilized as a support for a negative electrode in a metal hydride alkaline secondary battery. Or a copper metal foam is employed as a support for an electrode of alithium-ion secondary battery. The metal foam for the electrode support is a light weight, typically very flexible foam. The metal foam is particularly serviceable as an electrode support for a hydrogen storage alloy negative electrode, e.g., an electrode containing an active material of metallic alloy, such as an AB5 class of alloy or an AB2 class of alloy. As a support for an alkaline secondary battery negative electrode, the large pore metal foam may also serve as the negative cadmium electrode for a nickel-cadmium battery. As copper metal foam, the foam may further serve as the support for the positive or negative electrode, or for both, for a lithium-ion secondary battery.
Abstract:
A porous product, typically a metal foam sheet, is produced as a tailored, engineered product. The porous product can have enhancec strength, as well as more desirable electrical and mechanical properties. The product which first exists typically as a flexible, generally polymeric foam sheet in strip (12) form, which strip (12) is produced in the longitudinal direction, is stretched in a direction other than its direction of production. The porous product can have pores which would be anisotropic in form in usual production, which are stretched to at least substantially isotropic form. The product can even be tailored to have pores which are anisotropic in the direction of the stretch. Thus, an engineered product can be produced which, for example, as an open-cell metal foam prepared from a polymeric foam, can have conductivity, both thermal and electrical, as well as strength and ductibility, tailored for greater uniformity and performance.
Abstract:
A cell for the electrowinning of aluminum from molten salts has a cell bottom lining consisting partly of a refractory mass (4) and partly of carbon bodies (5). At least 30 % and preferably 50 % or more of the cell bottom area is occupied by the refractory mass (4). The carbon bodies (5) are level with the refractory mass (4) or are recessed therein.
Abstract:
A ceramic/metal composite material comprises a metal substrate with a surface ceramic coating, the substrate being an alloy comprising 10 to 30 % by weight of chromium, 55 to 90 % of nickel, cobalt and/or iron and up to 15 % of aluminum, titanium, zirconium, yttrium, hafnium or niobium. The interface of the substrate with the surface ceramic coating has an oxygen-barrier layer comprising chromium oxide. The surface ceramic coating may be an oxidised alloy of 15 to 75 % by weight of copper, 25 to 85 % by weight of nickel and/or manganese, up to 5 % by weight of lithium, calcium, aluminum, magnesium titanium, zinc, or iron and up to 30 % by weight of platinum, palladium and/or gold in which the copper is fully oxidised and at least part of the nickel and/or manganese is oxidised in solid solution with the copper oxide. The composite material may be used as substrate for an anodic cerium oxyfluoride coating used in aluminum electrowinning.
Abstract:
A coating for metallic faces comprises an alloy of aluminium with at least one of zinc, cadmium or manganese is proposed, whereby the alloy coating is applied onto the metal surface by means of electrodeposition using a non-aqueous electrolyte. The electrolyte comprises toluene as a solvent for chlorides of the alloy components. The coating may be used e.g. for corrosion protection.
Abstract:
A porous high surface area composite electroconductive catalytic material, particularly as electrocatalyst for electrolysis electrodes, comprises a porous pre-formed matrix which is a catalytic mixed crystal material of at least one platinum group metal oxide and at least one valve metal oxide throughout which a subsequently-added additional catalyst preferably consisting of at least one platinum group metal and/or oxide is dispersed by chemideposition in an oxidizing or reducing atmosphere preferably followed by an annealing post heat treatment. The porous matrix may be ruthenium-titanium oxide and the additional catalyst advantageously comprises at least two oxides of ruthenium, rhodium, palladium and iridium, other combinations being possible.
Abstract:
An aluminum production cell with a non-conductive cell bottom composed predominantly of alumina (1) has a plurality of vertical current collector plates or posts (3), e.g., of steel protected at their upper ends by a carbon body (4), e.g., a plate, slab or cap which contacts the cathodic pool of molten aluminum (10).