Thermodynamic Assessment of the CaO-NiO System Using the Quasi-chemical Cell Model of Kapoor-Frohberg-Gaye

The knowledge of the thermodynamic features of the NiO-CaO system is of fundamental importance to the modelling of metal-slag-refractory equilibrium of Ni-based alloys melting process in electric arc furnaces as well as for development a self-consistent multi-component thermodynamic database for nickel extraction from laterite ores. The existing assessment for liquid slag, based on the quasichemical model modified by Pelton and Blander cannot be in the SLAG database used by Thermo-Calc software which is based on a different thermodynamic model to slag phase. The present work presents the modelling of CaO-NiO using the quasichemical cell model of Kapoor-Frohberg-Gaye for the liquid slag phase. The data utilized for this modelling were activities, liquidus and solvus compositions as well as magnetic parameters of the phase NiO. The optimization was performed with the PARROT ® module of Thermo-Calc ® software. The results obtained, the phase diagram and the activities diagrams, are in good agreement with the literature data.