Distribution of Phosphorus between Liquid Iron and Fe<SUB>t</SUB>O-(CaO+MgO)-(SiO<SUB>2</SUB>+P<SUB>2</SUB>O<SUB>5</SUB>) Phosphate Slags

Abstract

Equilibrium phosphorus distribution between slag and liquid iron has been studied at the temperature range from 1 300°C to 1 680°C in order to know the effect of additives on the phosphorus equilibrium and the approximate validity of the regular solution model for the phosphate slag. The slag systems studied were of FetO-P2O5-MxOy ( MxOy = CaO, MgO, SiO2) ternary and of FetO-P2O5-CaO-MxOy (MxOy = MgO, SiO2) quaternary. In the wake of our previous two papers concerning the same experiments, the present paper deals with the results of phosphorus distribution between slag and metal. As the results, it was confirmed that the regular solution model was satisfied for all the experimental results including present work and the previous studies by other investigators, except for composition extreamly rich in iron oxide. The phosphorus content in metal and the activity of phosphorus pent-oxide in slag can be estimated within the accuracy of ± 10% by the model.