Thermodynamic Modelling Of Sulphide Capacity Of Ternary Silicate Slags

This article proposes a structural thermodynamic model of slags to estimate the sulphide capacity (C-s) of ternary silicate melts. Sulphide ion (S2-) is incorporated into the silicate structure by substituting quasi lattice sites in the slag for free oxygen ions (O2-). This structural model can take into account the effect of substituting one metal oxide for another in ternary systems, since it considers that each metallic oxide produces a de-polymerisation reaction of O degrees + O2- = 2 O- with a characteristic free energy change. The Cs of ternary silicates can be calculated by this model solely from the data of the binary sub-systems no ternary terms are required. A good agreement was obtained between the experimental and the model results for the ternary slags of the SiO2-CaO-MgO-MnO-FeO system.