SCI和EI收录∣中国化工学会会刊

中国化学工程学报 ›› 2024, Vol. 71 ›› Issue (7): 272-282.DOI: 10.1016/j.cjche.2024.03.012

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Effect of samarium doping on the activity and sulfur resistance of Ce/MnFeOx catalyst for low-temperature selective catalytic reduction of NOx by ammonia

Qiyao Zhang, Shuangshuang Zhang, Xu Hu, Yongmin Huang   

  1. Key Laboratory of Specially Functional Polymeric Materials and Related Technology, School of Chemistry and Molecular Engineering, East China University of Science and Technology, Shanghai 200237, China
  • 收稿日期:2023-11-18 修回日期:2024-03-10 出版日期:2024-07-28 发布日期:2024-08-30
  • 通讯作者: Yongmin Huang,E-mail:huangym@ecust.edu.cn
  • 基金资助:
    This research was supported by the Fundamental Research Funds for the Central Universities (222201817001) and Shanghai Sailing Program (21YF140800). Research Centre of Analysis and Test of ECUST provided analysis assistance.

Effect of samarium doping on the activity and sulfur resistance of Ce/MnFeOx catalyst for low-temperature selective catalytic reduction of NOx by ammonia

Qiyao Zhang, Shuangshuang Zhang, Xu Hu, Yongmin Huang   

  1. Key Laboratory of Specially Functional Polymeric Materials and Related Technology, School of Chemistry and Molecular Engineering, East China University of Science and Technology, Shanghai 200237, China
  • Received:2023-11-18 Revised:2024-03-10 Online:2024-07-28 Published:2024-08-30
  • Contact: Yongmin Huang,E-mail:huangym@ecust.edu.cn
  • Supported by:
    This research was supported by the Fundamental Research Funds for the Central Universities (222201817001) and Shanghai Sailing Program (21YF140800). Research Centre of Analysis and Test of ECUST provided analysis assistance.

摘要: The self-made MnFeO catalysts doped with cerium and samarium were prepared by impregnation method for low-temperature selective catalytic reduction (SCR) by NH3. In this work, the surface properties of the series of MnFe-based catalysts were studied. The results indicate Sm-modified catalyst have superior low-temperature SCR activity; NOx conversion maintained at nearby to 100% at 90 °C to 240 °C. In addition, The N2 selectivity of Sm doping remains above 80% in the range of 60 °C to 150 °C. In SO2 poisoning test, the NOx conversion can be remained >90% after 10 h of reaction. The XPS, NH3-TPD and H2-TPR results show the catalyst with Sm doping enhances the acid sites and oxidation catalytic sites of mixed oxides serves for improving oxygen vacancies and transfer electrons. In situ diffuse reflaxions infrared Fourier transformations spectroscopy (DRIFTS) results show that NOx is more easily adsorbed on the surface after Sm doping, which provided favorable conditions for the NH3-SCR reaction to proceed. The reaction at the catalyst surface will follow the L-H reaction mechanism by transient reaction test.

关键词: SCR, Sm doping, Catalyst, Sulfur resistance, In situ DRIFTS, Selectivity

Abstract: The self-made MnFeO catalysts doped with cerium and samarium were prepared by impregnation method for low-temperature selective catalytic reduction (SCR) by NH3. In this work, the surface properties of the series of MnFe-based catalysts were studied. The results indicate Sm-modified catalyst have superior low-temperature SCR activity; NOx conversion maintained at nearby to 100% at 90 °C to 240 °C. In addition, The N2 selectivity of Sm doping remains above 80% in the range of 60 °C to 150 °C. In SO2 poisoning test, the NOx conversion can be remained >90% after 10 h of reaction. The XPS, NH3-TPD and H2-TPR results show the catalyst with Sm doping enhances the acid sites and oxidation catalytic sites of mixed oxides serves for improving oxygen vacancies and transfer electrons. In situ diffuse reflaxions infrared Fourier transformations spectroscopy (DRIFTS) results show that NOx is more easily adsorbed on the surface after Sm doping, which provided favorable conditions for the NH3-SCR reaction to proceed. The reaction at the catalyst surface will follow the L-H reaction mechanism by transient reaction test.

Key words: SCR, Sm doping, Catalyst, Sulfur resistance, In situ DRIFTS, Selectivity