The thermal decomposition of the coal-derived pyrite was studied using thermogravimetry combining with Fourier-transform infrared spectroscopy (TG-FTIR) techniques to gain knowledge on the SO2 gas evolution process and formation mechanism during the thermal decomposition of the coal-derived pyrite. The results showed that the thermal
decomposition of the coal-derived pyrite which started at about 400 ◦C was complete at 600 ◦C; the gas evolved can be established by combining the DTG peak