GB321394A - Improvements in the production of compact masses from pulverulent metallic oxides - Google Patents

Abstract

321,394. Johnson, J. Y., (I. G. Farbenindustrie Akt.-Ges.). May 29, 1928. Electrodes.-Porous compact metal oxide masses suitable for electrodes particularly for use with an alkaline electrolyte are prepared by mixing a powdered metal oxide with a heavy metal or metals, at least partly in a finely divided condition, and oxidizing the metal by heating in a non- reducing atmosphere at a temperature below the melting point of the components or their mixture. The operation may be carried on with carbon dioxide or water vapour or with admixtures of these with gases such as carbon monoxide or hydrogen or with oxygen or gases containing oxygen. The treatment may be carried on in an inert atmosphere by using a higher oxide of a metal which becomes reduced to a lower oxide in oxidizing the metallic portion of the mixture. A metalic network such as wire gauze &c. or metal scales may be incorporated in the mass before heating. When the prepared masses are to be used they may be impregnated with salt solutions. Examples describe the preparation of masses comprising iron oxide, Fe3O4, from a mixture of this oxide and metallic iron powder in which, in one case, nickel gauze is embedded; also a mass comprising ferrous oxide made by heating ferric oxide, Fe2O3, with iron powder in a neutral atmosphere. Other metals which may be emploved are copper, chromium, manganese and cadmium.