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The thermal cracking process of oil sand bitumen was investigated via studying the thermal cracking behaviors and online-gas-releasing characteristics of its SARA fractions (saturates, aromatics, resins, asphaltenes) by using TG−FTIR. The results showed that the asphaltenes contributed the most to coke formation of oil sad bitumen according to its largest weighted coke yield compared with that of others. The online FTIR analysis for the gases evolved from the thermal cracking process of oil sand bitumen and its SARA fractions indicated that the gaseous products in the main reaction stage showed more complex composition than those in the volatilization stage, and predominantly consisted of CO 2 , CO, methane, ethylene, other light alkanes and olefins, light aromatics, and hydrogen sulfide. Moreover, the release behaviors of typical gaseous products (CO 2 , CO, methane, ethylene, and light aromatics) for oil sand bitumen and its SARA fractions were different due to the different composition and structure. The thermal-cracking kinetic parameters of oil sand bitumen and its SARA fractions were determined using the iso-conversional Friedman procedure at heating rates of 10 to 800 K/min. The activation energy of oil sand bitumen ranging from 93.74 to 215.99 kJ/mol in the whole thermal cracking process fell in between that of aromatics and resins. The variation of activation energy with the conversion rate for oil sand bitumen during the thermal cracking process was influenced by the interaction between SARA fractions.

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Recently, the renewed interest in the pyrolysis of municipal solid waste has been aroused. In this investigation, the pyrolysis behaviors and kinetics of typical municipal solid waste components and their mixture at high heating rates are studied by using thermogravimetry-Fourier transform infrared spectrometer (TG-FTIR). The TG/DTG results presented the different pyrolysis behaviors of each components and their mixture. The main volatiles were generated from 250 °C to 500 °C obtained by FTIR results. Moreover, the consistency between volatiles release and pyrolysis behavior was found through FTIR and TG. By comparing the experimental and calculated TG/DTG curves and volatiles released curves of mixed MSW, the interactions between individual components have been found, which performed as the interactions could accelerate the first pyrolysis reaction stage and postpone the second and third pyrolysis reaction stage. On the basis of the distributed activation energy model, the values of activation energy of individual components and their mixture were distributed between 123.73 kJ mol–1 and 312.56 kJ mol–1. Meanwhile, the frequency factor of them increased along with the activation energy. Overall, those findings can enrich a better comprehension of the MSW pyrolysis process.