Effect of Ni content on corrosion behavior of Ni/(10NiO-90NiFe 2O 4) cermet inert anode

Abstract

Ni/(10NiO-90NiFe 2O 4) cermet inert anodes with metal Ni content of 0, 5, 10, 15 and 20 (mass fraction, %) were prepared and their corrosion behavior in Na 3AlF 6-Al 2O 3 melts was investigated in laboratory electrolysis tests. The results indicate that the content of metal Ni in anodes has little effect on the steady-state concentration of impurities Ni and Fe in electrolyte and the values range in (114–173)×10 −6 and (287–385)×10 −6, but the content of impurities in the metal aluminum manifolds. There is preferential corrosion for metal Ni in NiO-NiFe 2O 4 based cermet anodes. Considering the corrosion resistance and electrical conductivity, the cermet containing 5%Ni (mass fraction) behaves best among NiO-NiFe 2O 4 based cermet anodes studied, and should be further studied.