THERMODYNAMICS OF FetO-P2O5 SLAGS SATURATED WITH SOLID IRON.

Abstract

As a first step in a study of the physical chemistry of dephosphorization in steelmaking, equilibrium measurements were made of hydrogen-steam mixtures of simple Fe//tO-P//2O//5 slags in equilibrium with solid iron at 1200 to 1450 degree C. The activities of Fe//tO and P//2O//5 in the slags were obtained from the data. The ferrous and ferric concentrations of slags, expressed as Fe** plus **3/Fe** plus **2, were decreased by the addition of P//2O//5. The isoactivity lines in FeO-Fe//2O//3-P//2O//5 slags at 1,600 degree C were calculated by applying the regular solution model of J. Lumsden to the experimental data.