Effect of Nb2o5 on the Electrical Conductivity of Cao-Sio2-Nb2o5-Ceo2-Caf2 (-Tio2) Melt

Electrical conductivity is a very important physical parameter in the process of electrolytic extraction of niobium from molten niobium-enriched slag or preparation of ferroniobium alloy by reduction melting separation in electric arc furnace. The effects of Nb2O5, CaO/SiO2 ratio and TiO2 on the electrical conductivity of CaO-SiO2-Nb2O5-TiO2-CeO2-CaF2 melt were studied by AC four-electrode method. The melt structure was studied by XPS to reveal the change rules of melt conductivity. The results show that the addition of Nb2O5 or increasing the CaO/SiO2 ratio in the melt can depolymerize the melt network structure and effectively improve the melt conductivity, and the activation energy of the conductivity is negatively correlated with the Nb2O5 content and the CaO/SiO2 ratio. With the increase of TiO2 content in the melt, the melt network structure polymerizes, the melt conductivity decreases, and the activation energy of conductivity also showed a decreasing trend.