Thermochemical Properties of Copper-Iron-Sulfur Alloy as Reference Metallic Phase for Analyzing Resulfurization

Abstract

The knowledge of sulfur distribution ratios between FeO-containing slag and hot metal is necessary for better understanding resulfurization in hot metal pre-treatment. To measure sulfur distribution ratios at temperature below the melting point of pure iron, copper-iron liquid alloy has been suggested as a reference metal equilibrated with slag. In the present study, the Henrian activity coefficient of sulfur in copper-iron liquid alloy was determined at 1573 K and 1673 K. The sulfur activity coefficient decreased with an increase in iron content; this result was not inconsistent with that reported by Alcock and Richardson. Negative logarithmic value for the sulfur activity coefficient indicated that the chemical affinity between iron and sulfur would be stronger than that between copper and sulfur.