HIGH-PURITY VANADIUM OBTAINING METHOD Russian patent published in 2004 - IPC

FIELD: metallurgy of rare refractory metals, namely metallurgy of vanadium, possibly for obtaining high-purity vanadium for production of vanadium-base special alloys.

SUBSTANCE: method comprises steps of alumo-thermic reduction of vanadium-containing raw material at adding to initial charge pelletized metallic calcium; melting reduced vanadium in electron-beam furnaces and then performing electrolytic refining of produced ingots in salt melt by two stages: during first stage refining at current intensity 0.03 - 0.1 KA for 4.0 -4.5 h and at number of cycles 2 - 20; during second stage refining at current intensity 0.8 - 1.0 KA for 4 - 8 h and at number of cycles 250 - 300. Refined vanadium powder is mixed with powder of metal selected from group: calcium and(or)rare-earth metals, and(or) aluminum and then it is compacted at pressure 2.0 - 2.1 t/sq. cm for making electrodes subjected in addition to three-stage remelting in electron-beam furnaces in vacuum. During first stage additional remelting of electrodes is realized at rate 5 - 6 kg/h, electric current 1.4 - 1.8 W and residual pressure 1 x 10^-4 ; during second stage : at rate 7 - 8 kg/h, electric current 1.6 - 2.0 A and residual pressure 4 x 10^-5 - 5 x 10^-5 ; during third stage at rate 8 - 10 kg/h, electric current 1.7 -2.2 A and residual pressure 2 x 10^-5 - 5 x 10^-6 Hg.

EFFECT: obtaining vanadium of higher purity degree.

5 cl, 1 ex