Influence of Ce-doping on MnOx-ZSM-5 catalysts for the selective catalytic reduction of NO/NO2 with NH3

• Published in: Reaction kinetics, mechanisms and catalysis Vol. 125; no. 2; pp. 1071 - 1084
• Main Authors: Yang, Xiaochu, Xiao, Haiping, Liu, Jun, Wan, Zhentian, Wang, Tao, Sun, Baomin
• Format: Journal Article
• Language: English
• Published: Cham Springer International Publishing 01.12.2018
• Subjects: Catalysis; Chemistry; Chemistry and Materials Science; Industrial Chemistry/Chemical Engineering; Physical Chemistry; Fast SCR; NO oxidation; CeO; MnO
• ISSN: 1878-5190; 1878-5204
• DOI: 10.1007/s11144-018-1460-7

A series of MnO x -CeO 2 /ZSM-5 catalysts with different Ce loadings were prepared through the impregnation method and characterized by BET, XRD, SEM, H 2 -TPR, and XPS. The performances of selective catalytic reduction (SCR) of NO/NO 2 with NH 3 and NO oxidation over MnO x -CeO 2 /ZSM-5 catalysts were investigated. The result showed that the MnO x dispersions, redox abilities and proportions of Mn 4+ of catalysts were enhanced by the doping of CeO 2 . However, the excessive Ce loadings led to the accumulation of active components on the catalyst surface. The sample with Ce/Mn molar ratio of 0.39 exhibited the best SCR performance, the NO x conversion achieved 95.4% at 150 °C, and maintained higher than 95% in a wide operating temperature range (150–350 °C). MnO x -CeO 2 /ZSM-5 also exhibited considerable catalytic performance of NO oxidation, the maximum conversion of NO achieved 56.5% at 350 °C.