SCR of NOx by NH3 over MnFeOx@TiO2 catalyst with a core-shell structure: The improved K resistance. Issue 5 (October 2019)

• Record Type: Journal Article
• Authors: Huang, Chun-ying; Guo, Rui-tang; Pan, Wei-guo; Sun, Xiao; Liu, Shuai-wei; Liu, Jian; Wang, Zhong-yi; Shi, Xu
• Is Part Of: Journal of the Energy Institute. Volume 92:Issue 5(2019)
• Page Start: 1364
• Page End: 1378
• Publication Date: 2019-10
• Subjects: SCR -- MnFeOx@TiO2 catalyst -- Core-shell structure -- K resistance; Power (Mechanics) -- Periodicals; Power resources -- Periodicals; Fuel -- Periodicals; 621.04205
• DOI: 10.1016/j.joei.2018.09.005
• Languages: English
• ISSNs: 1743-9671

Abstract

Abstract: Some fly ash components such as K could seriously weaken the catalytic performance of SCR catalyst. In this study, the core-shell-structured MnFeOx@TiO2 catalyst is synthesized by dipping deposition method and used for the NH3 -SCR reaction. The results show that MnFeOx@TiO2 catalyst exhibits higher K resistance than MnFeOx/TiO2 catalyst prepared by impregnation method. And the correlativity between the core-shell morphology and K resistance of MnFeOx@TiO2 catalyst is studied by TEM, N2 adsorption, XRD, XPS, TPR, TPD and in situ DRIFT. It can be found that the shell of TiO2 has a protective effect on the active species in MnFeOx@TiO2 catalyst. And the core-shell structure of MnFeOx@TiO2 catalyst can produce more Mn 4+ and chemisorbed oxygen species on its surface, improving reducibility and surface acidity. Moreover, the core-shell structure of MnFeOx@TiO2 catalyst is beneficial to the adsorption of NH3 and the formation of NO2, resulting in the favored SCR reaction via the Eley−Rideal and the Langmuir−Hinshelwood routes. Therefore, MnFeOx@TiO2 catalyst shows excellent K tolerance. Graphical abstract: Image 1 Highlights: The core-shell structure of MnFeOx@TiO2 catalyst could protect the active species from the contact with K species. The morphology of MnFeOx@TiO2 catalyst is propitious to the conversion from to NO2 . The SCR process over MnFeOx@TiO2 catalyst was advanced via both E-R and L-H modes.