FR1486217A - - Google Patents

Abstract

1,147,754. Preventing fouling of marine structures; electrolysis; alloys. VICKERS Ltd. and CATHODIC & ELECTROLYTIC ENGS. CO. Ltd. July 6, 1966 [July 8, 1965], No.29085/65. Headings C7A, C7B and C7E. Fouling of a surface of a marine structure is prevented or eliminated by treating the surface with water electrolyzed using an anode and cathode electrically insulated from the surface, the anode providing during electrolysis ions of materials toxic to marine growths such as algae, bacteriological slime, mussels, barnacles or other animal growth, and comprising by weight at least “% As, ¢% Sb, or in the case of both arsenic and antimony together “% of each of As and Sb. The bulk of the anode may be of Cu, Fe or Al. For anodes of Cu, the toxic metal content by weight is “ to 2% As, ¢ to 6% Sb, or “ to 2% As together with ¢ to 3% Sb. For anodes of Fe, the toxic metal content by weight is “ to 2% As, ¢ to 6% Sb, or “ to 2% As together with ¢ to 4% Sb. For anodes of Al, the toxic metal content by weight is “ to 3% As, ¢ to 10% Sb, or “ to 2% As together with ¢ to 6% Sb. Typically there may be used in combination a Cu-As anode and an Al anode insulated from each other and the current to each separately controlled. If desired the two anodes may be in the form of a unitary structure but insulated from each other. Electrolysis e.g. of seawater may be effected ina container remote from the surface to be protected or in the medium in which the surface to be protected is immersed, the electrodes being disposed to ensure a passage of the toxic ions over the surface to be protected. If a separate container is used for electrolysis the container may form the cathode so the sea water electrolyzed may be heated. Examples are given of preventing fouling of ship hulls.