Cobalt prodn. from oxidic material - by smelting using reducing gas plasma jet

摘要

Cobalt is mfd. by plasma jet heating of oxidic cobaltiferous primary material to the m. pt. of cobalt and reducing the cobalt oxides to cobalt in the presence of a reducing gas, followed by desulphurisation of the resulting metal bath and removal of dissolved gases. The plasma jet is produced by passing the reducing gas across an electric discharge zone and heats the primary material to 1450-1580 deg. C. The amt. of reducing gas is 1.15-1.5 times the stoichiometric amt. for redn. of the cobalt oxides. The process gives high yields of high quality cobalt. Use of a reducing gas, instead of solid carbonaceous reductant of the electric arc and carbothermic redn. processes, gives improved working conditions and less environment pollution (by reducing CO evolution), improves reaction capacity, reduces reduction time and avoids subsequent operation such as decarburisation and deoxidation.