Phase Equilibria of CaO-SiO2-La2O3-Nb2O5 System in Reducing Atmosphere

In the current work, phase equilibria of CaO-SiO2-La2O3-Nb2O5 system at 1200 °C in reducing atmosphere (PO2 = 10−15 atm) was investigated according to melting separation process for extracting lanthanum and niobium resources from Bayan Obo tailing. High temperature equilibrium experiment, scanning electron microscope, energy dispersive spectrometer (SEM-EDS) were used determine compositions phases. According experiment results, ascertained isothermal diagram constructed. The research results not only play an important role guiding development extraction process, but also enrich thermodynamic data relevant silicate slag systems.