A. Baikov Institute of Metallurgy and Materials Science, Moscow, Russia:

+A. A. Palant
S. V. Palant, Engineer-Researcher

V. A. Bryukvin, Head of Laboratory of Pyrometallurgy, e-mail: brukvin@imet.ac.ru
A. O. Bolshikh, Junior Researcher

Manufacturing of solid alloys WC – Co uses the corresponding oxides of tungsten and cobalt as raw products. These products are reduced by hydrogen with following carbidization and calcination. For the purpose of production of solid alloys, cobalt is obtained during oxalic process by sedimentation of slightly-soluble CoC₂O₄ from nitrate mediums. The process is characterized by rather complete release of cobalt from the solution (with residual of <0.05 g/l of Со). Such technology is characterized by high cost of oxalic acid and its deficiency, because main amounts of this acid are used in food industry. This article is devoted to the operating-parametrical processing of ammoniaautoclave sedimentation of cobalt from nitrate solutions and to research of physical-chemical characteristics of obtained product by methods of X-ray phase, dispersion and chemical analysis. There was researched the process of obtaining of cobalt oxide by ammoniaautoclave method. There were carried out the physical-chemical researches of the process of autoclave sedimentation of cobalt from sulfate, chloride and nitrate solutions. There was made a definition that pure Co₃O₄ can be obtained only from nitrate solutions in the conditions of ammonia autoclave process with the temperature of 240 ^oС, pressure of 3.24 MPa, 30 minutes longevity and рН = 9.5. In the defined process mode, Co extraction in sediment reaches 99.9% with its residual content in mother liquor (0.018 g/l). Coarseness of obtained cobalt oxide powder is 110 nm, which corresponds to the possibility of its use for the production of solid alloys.

1. Reznichenko V. A., Palant A. A., Morozov A. A. et al. Kompleksnoe ispolzovanie rud i kontsentratov (Complex use of ores and concentrates). Moscow : Nauka, 1989. 172 p.
2. Shapiro K. Ya., Sobol S. I., Palant A. A. et al. Sposob polucheniya poroshka kobalta (Method of obtaining of cobalt powder). Certificate of authority USSR, No. 1511969. Applied: December 14, 1987. Published in 1989.
3. Shapiro K. Ya., Ivanova A. V., Palant A. A. et al. Sposob polucheniya poroshkov kobalta (Method of obtaining of cobalt powders). Certificate of authority USSR, No. 1548951. Applied: August 04, 1988. Published in 1989.
4. Khimicheskaya entsiklopediya : v 5 tomakh (Chemical encyclopedia : in 5 volumes). Under the editorship of I. L. Knunyants. Moscow : Sovetskaya entsiklopediya, 1990. Vol. 1. 673 p.