Activity model and its application in CaO-FeO-SiO₂-MoO₃ quarternary system

The activity model of CaO-FeO-SiO₂-MoO₃ quarternary system was established according to the coexistence theory of slag structure and the reduction thermodynamics of molybdenum oxide was discussed by applying this model. The activities of SiO₂and MoOs decrease, while that of CaO increases with increasing the basicity of slag. Among SiC, [C] and [Si] reactants, the reducing capability of SiC is the strongest, while that of [C] is the poorest at a high temperature (about 1873 K). It is advantageous to increase the yield of molybdenum by increasing the content of [Si] or [C]. Controlling of basicity of slag can prevent the oxidation loss of molybdenum.