GB157871A - Improvements in electrodes for use in electrolysis - Google Patents

Abstract

157,871. Chile Exploration Co., (Assignees of Fink, C. G.). Jan. 21, 1920, [Convention date]. Alloys.-An electrolytic electrode is made of an alloy containing cobalt and silicon. There may also be added a metal, such as manganese, facilitating disengagement of the electrolytic oxygen, and a hardening-metal such as chromium, tungsten, molybdenum, or uranium. Sufficient carbon may be added to produce a slight formation of graphite. Good results are got with the following composition:-11.5 to 13 per cent of silicon, 4-6 per cent each of manganese and chromium, 0.8-1.2 per cent of carbon, and the rest cobalt. From 5 to 30 parts of the cobalt may however be replaced by manganese, 5-12 by chromium, or 5-8 by nickel. The cobalt used may contain 4-7 per cent of nickel and iron as impurities. Maximum bending strength is obtained with 12-15 per cent cf silicon. Carbon should generally be between 0.5 and 1.2 per cent, silicon between 7 and 20 per cent, manganese between 3 and 45 per cent, and chromium or its equivalent between 4 and 10 per cent. The carbon in the form of charcoal may be added to the molten cobalt, followed by silicon and manganese. together. The addition of silicon produces evolution of heat, and should be gradual; carbide of silicon may be used, or the silicon mav be first combined with a small proportion of cobalt. Alternatively, mixed oxides of cobalt, manganese, and chromium may be reduced. The final alloy is stated to consist of particles of an alloy of high conductivity but liable to corrosion, enclosed in a substance, probably cobalt silicide, or low conductivity but high resistance to corrosion. The anodes can be used in solutions containing nitrates and chlorides, and at temperature up to 60‹ C.