Pyrolysis Characteristics of Oil Shale Semi-coke and Its Extracted Bitumen

Abstract Fushun oil shale semi-coke and its extracted bitumen were prepared for analyzing their pyrolysis characteristics by TG―DTG, TG―FTIR, and Py―GC/MS. Semi-coke was the residue of oil shale pyrolyzed to 450 °C, and extracted bitumen was the organic matter extracted from semi-coke with [Bmim]Cl/NMP mixed solvents. Gaussian fitting method was used to analyze the proportions of bond cleavage reactions occured during the pyrolysis to 700 °C at a heating rate of 20 °C/min. Results showed that 3―4 kinds of bond cleavages were mainly involved. The outstanding pyrolysis behaviors were contributed by the cleavages of Cal―Cal and weak bonds (volatilization). The kinetic parameters based on Coats―Redfern method were calculated from the points for each pyrolysis stage and bond cleavage reaction. The evolution processes of typical gaseous products and distributions of flash pyrolysis products were displayed in detail, exhibiting the prominent roles of aliphatic compounds, CH4, and CO2. Moreover, the releases of the typical gaseous products for semi-coke tended to occur at higher temperatures.