Effect of TiO<sub>2</sub> Addition and Cooling Rate on Crystallization Behavior of Separated Slag Containing Low-grade RE

With the continued exploitation and utilization of high-grade rare earth ores, it is increasingly important to extract earths from separated slag containing low-grade earth. The X-ray powder diffraction, scanning electron microscopy, probe micro-analyzer confocal laser microscopy were used explore influence TiO2 cooling rate on crystallization CaO-SiO2-TiO2-10 wt% P2O5-8 Nb2O5-5 CeO2-5 CaF2 system. In this study, britholite was precipitated selectively as Ce-enriched phase. When added at less than 12 wt%, promoted crystallize meanwhile Ca2Nb2O7 suppressed. However, CaTiSiO5 inhibited growth when content exceeded 15 wt%. non-isothermal kinetics had also been investigated for varied 0-18 10-40°C/min, respectively. continuous transformation diagram relative crystallinity primary crystals constructed. Based observation measurement process, modified Avrami model applied determine mode with 9 addition. It constant nucleation one-dimensional diffusion controlled. Considering crystals, 20–30°C/min preferred be reasonable parameter during stage.