Study on the calcination experiments of rare earth carbonates using microwave heating

Abstract

The heating behavior and effect of experimental parameters like holding time, calcination temperature and microwave power on the weight loss of the mixed rare earth carbonate using microwave heating have been studied, also characterized by X-ray diffraction, thermogravimetry-differential scanning calorimetry, scanning electron microscopy (SEM), particle analysis and Fourier transform infrared (FT-IR). The results show the following: rare earth oxides are obtained at 850°C for holding 1 h; FT-IR analysis indicates that the vibration absorption peak of carbonate disappears after calcination using microwave, confirming the feasibility of microwave calcination for the rare earth carbonates; SEM shows that the rare earth oxides have the characteristics of better and finer particles, have better dispersion and have surface that is more loose and porous than that of products using conventional calcination; particle analysis indicates that average size (D50) of microwave heating is 1.52 μm, which is smaller than conventional calcination of 7.6 μm.

Keywords

• microwave calcination
• rare earth carbonates
• rare earth oxides