Thermodynamic activities of "FeO" in some binary "FeO"-Containing slags

In the present investigation, experimental measurements of the thermodynamic activities of iron oxide in the Al2O3-"FeO", CaO-"FeO" and "FeO"-SiO2 systems were performed in the temperature range 1823-1873 K by using gas equilibration technique. The molten slag, kept in a Pt-crucible was brought to equilibrium with a gas mixture of known oxygen partial pressure. A part of the Fe from the "FeO" was reduced during the equilibration and got dissolved in the Pt phase. The samples were quenched after the required equilibration time and the slag phase as well as the platinum crucible was subjected to chemical analysis. The activities of "FeO" in the slag were calculated from the experimental data using thermodynamic information on the Fe-Pt binary metallic system generated and assessed earlier. The experimental results are compared with earlier thermodynamic studies of the slag systems. Reassessment with the KTH slag model is performed and the results are compared with other thermodynamic models, viz. F*A*C*T(TM) and Thermo-Calc(TM) respectively. The experimental activities predicted by the KTH slag model are in good agreement with the experimental data available in the literature. A general agreement between the various models is also observed.