PARTITIONS OF NITROGEN AND SULFUR BETWEEN CAO-AL2O3 MELTS AND LIQUID-IRON

Nitrogen and sulfur distribution ratios between CaO-Al2O3 slags and Fe-0.0001 33mass%Al alloys were measured in the temperature range of 1 823 to 1 923 K, using an Al2O3 and CaO crucibles. The distribution ratios under a CaO crucible were higher than those under an Al2O3 crucible, and increased with an increase of Al content. Nitride and sulfide capacities defined by C(N3) = (mass%N) . P(O2)3/4/P(N2)1/2 and C(S 2-) = (mass%S) . P(O2)1/2/P(S2)1/2, respectively, which were obtained by using the reported values for activity of Al2O3, agreed well with those directly measured in a gas-slag experiment under an Al2O3 crucible, but disagreed with those under a CaO crucible. Activities of Al2O3 in the CaO-Al2O3 melts saturated with CaO were evaluated based on the results in the gas-slag experiments.