Thermodynamic modeling of the UO2-CaO phase diagram

A thermodynamic modeling of the UO2-CaO phase diagram was performed with experimental data available in the literature. A relatively simple approach is used to model the solution phases, which are treated as the regular and the sub-regular solutions of the end-members. A consistent set of optimized interaction parameters was derived for describing the Gibbs energy of each phase in this system leading to a good fit between calculation and experimental data. A tentative phase diagram was presented by calculating the liquidus, solidus, and solvus curves. Also, the lattice stabilities and the activities of each component were evaluated from the present thermodynamic modeling.