Comparison of the Electronic Conduction Mechanism in MnOx-CaO-SiO2 and FeOx-CaO-SiO2 Slag Systems

Abstract

The electrical and electronic and ionic transference numbers were measured for slags in the system MnO-CaO-SiO2 using the stepped potential chronoamperometry method. Transference numbers were measured over a range of oxygen partial pressure to evaluate the effect of MnO-CaO-SiO2. The data were compared with previously measured data for the FeO-CaO-SiO2 system. Data were found to fit well, the Diffusion Assisted Hopping Model for electronic conduction previously develop in the authors' laboratory. The only adjustable parameter employed in fitting the data to this model, was, r*, the maximum spacing at which hopping can occur. A single value for this parameter was used for all manganese data. The value of r* obtained for the MnO-CaO-SiO2 system was slightly smaller than that for the FeO-CaO-SiO2 system which is in keeping with the relative magnitude of the third ionization energies for Fe and Mn.

Keywords

• slags
• electronic conductivity
• transference number
• manganese