ASSESSMENT OF ALUMINUM OXYGEN EQUILIBRIUM IN LIQUID-IRON AND ACTIVITIES IN CAO-AL2O3-SIO2 SLAGS

The equilibrium constant K(Al) for the reaction: 2Al+30=Al2O3(s) and the first-order interaction parameter e(Al)O were estimated at 1 873 K by using the values for the contents of oxygen, aluminum and other components obtained in slag-metal equilibrium experiments and those for activity of alumina, along with the respective interaction parameters. The values for log K(Al) and e(Al)O were found to be 13.3 +/- 0.59 and -6.83 +/- 0.07, respectively. Activities of slag components in the CaO-Al2O3-SiO2 system were also evaluated at 1 873 K from the values for nitride and sulfide capacities coupled with nitrogen and sulfur distribution ratios. These results were discussed by comparing with previous values.