Verfahren und Vorrichtung zur Reduktion feuerfester Metalloxide

1313845 Reduction of molybdenum or tungsten oxide UNITED KINGDOM ATOMIC ENERGY AUTHORITY 14 April 1970 [23 April 1969] 20865/69 Heading C1A [Also in Divisions C7 and F4] Tungsten or molybdenum oxide is reduced by contacting a bed of the hot oxide with a current of CO and recirculating to the bed the mixed monoxide and dioxide off-gases over a reducing agent for reducing carbon dioxide to monoxide. The product of the reduction may be the metal or its carbide depending on the temperature and CO 2 concentration in the reaction. Tungsten carbide is specified as being obtained by reduction of the oxide at 850‹ C. and a CO 2 core below 20% v/v. At higher concentrations the metal is produced. Apparatus claimed for carrying out the process of the invention comprises a kiln 1 heated by external heating means 3 and a means 4 together with connecting pipes for passing off gases from the kiln 1 through a vessel 5 for containing the reducing agent and back to the kiln 1.