The sulfur partition ratio with Fe-CSAT melts and the sulfide capacity of CaO-SiO2-Na2O- (Ai2O3) slags

The sulfur partition ratio between slag and carbon saturated iron and the sulfide capacity of CaO-Na₂O-SiO₂ slags and a 48 pet CaO-45 pet Al₂O₃-7 pet SiO₂-(Na₂O) slag have been mea-sured at 1400 °C. The addition of Na₂O to a CaO-SiO₂ slag increases the sulfur partition ratio and the sulfide capacity; however, Na₂O at low concentrations has no measurable effect on the sulfide capacity of a CaO-Al₂O₃-SiO₂ slag. To convert the sulfur partition ratio to the sulfide capacity, the oxygen potential was calculated assuming equilibrium between iron in the alloy and FeO in the slag with the activity of FeO calculated via a regular solution model. The optical basicity may be used to correlate the data, but at high Na₂O contents the data do not adhere to the correlation previously developed for CaO-based slags. Formerly Graduate Student at Carnegie Mellon University