Ar-H<SUB>2</SUB>プラズマアークによるバナジウムの精錬

Abstract

To prepare high-purity vanadium metal, the investigation of deoxidation and decarburization of a crude vanadium containing a small amount of carbon and oxygen, obtained by the carbothermic reduction of vanadium oxide, was made by an Ar-H2 (5-25 vol.%) plasma arc smelting.The results obtained are as follows:1) Carbon and oxygen contents in a crude vanadium obtained by the carbothermic reduction of vanadium oxide were dependent, and controlled on the mixing ratio C/V2O5.2) Remarkable deoxidation from a crude vanadium was found in the Ar-H2 plasma arc smelting, but decarburization was insufficient, as expected by the thermodynamical calculations.3) Massive vanadium metal of about 99.6% purity, with a hardness of Hv=180, was obtained by the Ar-H2 (25 vol.%) plasma arc treatment of a crude vanadium with high oxygen and low carbon content.4) Deoxidation reaction was mainly due to the reaction between oxygen in vanadium and hydrogen molecule and/or atom at high-temperature, and the contribution of metal suboxide volatilization to deoxidation was small so that loss of vanadium was reduced. Therefore over all metal yields of above 85% were typical.