Journal of the Korean Society of Mineral and Energy Resources Engineers ISSN:2288-0291(Print) 2288-2790(Online) 한국자원공학회지

A fundamental study on the volatilization purification method, a pyrometallurgical purification technology, was carried out to examine the removal of impurities from vanadium pentoxide (V₂O₅). From the thermodynamic analysis, it was expected that impurities contained in V₂O₅ could be removed into the gas phase while holding it at temperatures over 300°C for P₂O₅ and at over 600°C for NaOH and KOH, because of their high vapor pressures. Experiments were carried out in the temperature range of 600–1,100°C and a holding time range of 15–60 min under atmospheric and reduced pressures. The range of reduced pressure was 7.9×10^-2–1.1×10^-1 atm under an argon atmosphere. By comparing the thermodynamic analysis with the experimental results, it was verified that impurities such as SO₃, P₂O₅, NaOH, and KOH were effectively removed from V₂O₅ regardless of the pressure conditions of the furnace. At the optimum conditions, V₂O₅ with a purity of 99.6 wt% was manufactured from V₂O₅ with a purity of 99.2 wt%.