METHOD FOR OBTAINING PURE NIOBIUM Russian patent published in 2013 - IPC C22B34/24 C22B5/04 C22B9/16 

FIELD: metallurgy.

SUBSTANCE: method involves reduction of niobium pentoxide by means of aluminium and calcium so that rough niobium billets are obtained, their heat treatment and further multiple electron-beam melting of rough billets so that mainly non-oxidised fumes are formed after it is completed. Reduction is performed so that the above fumes are added. Prior to reduction the fumes formed after performance of the second and the next electron-beam melts are heated to the temperature of 600-800°C at residual pressure of not more than 0.1 mm Hg at least during one hour and hydrated at least during 12 hours. After hydration they are crushed till the size of ~1 mm, dehydrated and added to initial niobium pentoxide in the amount of 5-10% in relation to the weight of niobium pentoxide. Reduction process is performed at the following component ratio, wt %: Nb₂O₅:Al:Ca=1:0.22-0.24:0.27-0.29.

EFFECT: reduction of niobium pentoxide consumption for reduction operations and prime cost of products without deterioration of quality of refined niobium.

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