Catalytic pyrolysis of tar-rich coal for coal tar to light oil with catalysts of modified granulated blast furnace slag

Parts of China are abundant in tar-rich coal (pyrolysis yield of coal tar is more than 7%), if it can be converted into high-quality tar, it is a reliable means to deal with energy problems. This paper takes tar-rich coal in Shenmu area and uses modified granulated blast furnace slag (GGBS) for catalytic pyrolysis, and the effects of different metal oxides and different amounts of modified GGBS on tar yield are explored. The fractions of pyrolysis tar are analyzed by gas chromatography, and the pyrolysis cokes (PC) are analyzed by Fourier transform infrared (FTIR) and X-ray diffraction (XRD). The thermodynamics of modified GGBS with pyrolysis gas and pyrolysis tar of the reaction process is calculated by HSC Chemistry software. The results show that the yield of coal tar increased after catalytic pyrolysis, and the fraction of coal tar is directional transformation to phenolic oil. The modification of GGBS with CaO, Al 2 O 3 , and Fe 2 O 3 has a good effect on increasing tar production and improving oil quality. Especially for CaO@GGBS, it can increase the tar yield of tar-rich coal to 15.12% with 97.72% phenol oil, far exceeding the current limit of coal pyrolysis tar yield of around 5%. The crystal structure of pyrolysis coke indicates that different reactions occurred. The possible reaction and equilibrium concentration of the reaction of pyrolysis tar under catalytic pyrolysis are revealed by HSC Chemistry. This provides a foundation for the high-value utilization of tar-rich coal and the comprehensive utilization of GGBS in the future.