GB396717A - Improvements in the manufacture and production of cobalt nitrosocarbonyl - Google Patents

Abstract

Cobalt nitrosocarbonyl and/or cobalt nitrosyl are obtained by acting with nitric oxide, if necessary together with carbon monoxide, upon metallic cobalt or a material containing cobalt in the metallic state or in a state from which it can be reduced to metallic cobalt by the reducing gases present, such as excess of carbon monoxide. The gas mixture may also contain inert gases such as nitrogen. When cobalt nitrosocarbonyl is being produced the nitric oxide may be wholly or in part replaced by substances supplying it such as nitrates or liquid solutions of nitric oxide. Normal, increased or reduced pressure may be employed with room temperature or elevated temperatures not exceeding 250 DEG C. Ores or waste products containing a small amount of cobalt may be converted into the nitroso compounds; the conversion may be preceded by pretreatment such as roasting, conversion into oxides, loosening in order to increase superficial area or reduction to the metallic state. Substances such as copper which facilitate the production of the nitroso compounds may be added. The nitroso compounds may be burnt, or thermally decomposed in the presence of inert gases, to form cobalt oxide, thermally decomposed in the presence of reducing gases such as hydrogen to form metallic cobalt or treated with strong mineral acids to form cobalt salts. According to examples, (1) a precipitate obtained by adding lime to a solution of cobalt sulphate is reduced with hydrogen at 350 DEG C. and then treated with carbon monoxide containing 1 per cent nitric oxide at 60-70 DEG C. and atmospheric pressure to produce cobalt nitroso carbonyl; (2) cobalt nitrate is evaporated to dryness with lime and the resulting mass is treated with flowing carbon monoxide at 240 DEG C. and 200 atmospheres pressure to produce cobalt nitroso carbonyl; (3) an industrial waste containing calcium sulphate and oxides of iron, copper and cobalt is dried, reduced by hydrogen at 380 DEG C. and treated with carbon monoxide containing 5 per cent nitric oxide at 160-180 DEG C. to produce cobalt nitroso carbonyl; (4) a reduced material prepared as in the preceding example is treated at atmospheric pressure and 150 DEG C. with carbon monoxide containing 10 per cent nitric oxide to produce a mixture of cobalt nitroso carbonyl with cobalt nitrosyl; (5) a reduced material prepared as in example (3) is treated at atmospheric pressure and 150-180 DEG C. with a mixture of nitrogen and nitric oxide to produce cobalt nitrosyl. The Provisional Specifications describe also the employment of nitrogen oxides in general in the process.ALSO:Cobalt nitrosocarbonyl and/or cobalt nitrosyl, obtained by the action of nitric oxide together if necessary with carbon monoxide upon metallic cobalt or materials capable of yielding metallic cobalt, may be thermally decomposed in the presence of reducing gases such as hydrogen to produce metallic cobalt.