The thermal activation process of coal gangue selected from Zhungeer in China

The thermal behavior of coal gangue selected from Zhungeer, Inner Mongolia Autonomous Region of China, was investigated by X-ray diffraction (XRD), Fourier transform infrared (FT-IR) spectroscopy, thermogravimetry (TG), derivative thermogravimetry (DTG), and scanning electron microscope (SEM). The XRD data indicated that the mineral compositions of the coal gangue were kaolinite, boehmite, and quartz. The coal-gangue sample was considered as belonging to a typical mixture of kaolinite and boehmite. The XRD and FT-IR spectra clearly showed that the structural changes and dehydroxylation of coal gangue occurred with increased temperature from 100 to 900 degrees C. The reaction activity of coal gangue could be effectively improved by calcination. The calcined coal gangue contained considerable active amorphous Al2O3 and SiO2 and had significant loss on ignition. The optimum activation temperature range of coal gangue was from 600 to 700 degrees C. The dissolution contents of SiO2 and Al2O3 were 92.31 and 64.44 %, respectively, when the calcination temperature at 700 degrees C.