Effect of shear rate on the rheological and crystallization behaviors of CaO-SiO2-CaF2-Ce2O3 slag melt at high temperature

The irreplaceability role of rare earths in high-performance materials, such as ceramics, highlighting the significance of rare earth extraction. Strengthening the crystallization growth of the rare earth phase in rare earth slag is crucial for ensuring effective subsequent rare earth enrichment and separation. However, viscosity plays a major role in the characteristics of high-temperature melts and the crystallization process. In this study, an internal column rotation method was used to measure the viscosity of CaO-SiO 2 -CaF 2 -Ce 2 O 3 slag melts. The effect of shear rate on the rheological behavior of CaO-SiO 2 -CaF 2 -Ce 2 O 3 slag with varying Ce 2 O 3 and CaF 2 contents, and CaO/SiO 2 ratio was investigated by examining the viscosity evolution during the rare earth crystallization growth process. The rheological behavior of the CaO-SiO 2 -CaF 2 -Ce 2 O 3 slag was elucidated in regions of liquid phase, low solid phase, and high solid phase, providing insight into the viscosity changes of non-Newtonian flowing melts. Based on this, the effect of shear rate on the crystallization behavior of rare earth phases was investigated to provide a basis for improving the subsequent separation of rare earth phases.