Influence of the valence state change of iron oxidation for pyrolysis by using density functional theory

• Published in: Applied surface science Vol. 478; pp. 313 - 318
• Main Authors: Zhao, Yue, Liu, Jiang-Tao, Liang, Wen-Sheng, Huang, Wei, Zuo, Zhi-Jun
• Format: Journal Article
• Language: English
• Published: Elsevier B.V 01.06.2019
• Subjects: Benzoic acid; Catalytic pyrolysis; DFT; Fe compounds; Benzoic acid; Fe compounds; DFT; Catalytic pyrolysis
• ISSN: 0169-4332; 1873-5584
• DOI: 10.1016/j.apsusc.2019.01.254

The influence of valence state change of catalysts during pyrolysis is studied by density functional theory (DFT). In this study, benzoic acid (C6H5COOH) is a coal-based model compound, and Fe compounds (i.e., α-Fe2O3, Fe3O4, FeO, and Fe) serve as catalysts. The highest energy barrier of C6H5COOH pyrolysis on Fe3O4 and FeO is lower than that of C6H5COOH pyrolysis, but the highest energy barrier of C6H5COOH pyrolysis on α-Fe2O3 and Fe is similar to that of C6H5COOH pyrolysis. Results show the presence of an induction period for C6H5COOH catalytic pyrolysis by using Fe compounds as catalyst. Catalytic activity increases when α-Fe2O3 is reduced as Fe3O4 and FeO. Finally, the catalyst is deactivated as Fe3O4 and FeO are further reduced to metallic Fe. [Display omitted] •The catalyst is deactivated with reaction time increasing.•There is the induction period for C6H5COOH catalytic pyrolysis using Fe compounds.•Fe3O4 and FeO show the best activity.•α-Fe2O3 and Fe have not catalytic pyrolysis for C6H5COOH.