Preferred enhancement of fast-SCR by Mn/CeSiOx catalyst: Study on Ce/Si promotion and shape dependence

A series of Mn/CeSiOx catalysts were synthesized to investigate the Ce/Si ratios and morphology effect of Ce/ SiOx support for the selective catalytic reduction (SCR) of NO with NH3 at low temperature. The characterization and catalytic test showed that the 0.3Mn/Ce8Si2Ox-R catalyst exhibits high NOx conversion at low temperature. The Ce/Si ratio was 8/2 over the 0.3Mn/Ce8Si2Ox-R catalyst, increasing the surface acidity and inhibiting the side reaction of NH3. The {110} and {100} facts of the nanorod structure are rich in Ce3+ species and oxygen vacancies for the SCR reaction. Moreover, the citric acid method was employed on 0.3Mn/Ce8Si2Ox-R-CA to improve the interaction between Mnn+ and Ce8Si2Ox-R and enhance the strength of surface acidity, leading to the highest NOx conversion and Fast-SCR process. During the suppression effect of SO2 or HCl on catalytic activity, the 0.3Mn/Ce8Si2Ox-R-CA catalyst shows higher poison resistance to HCl than SO2.

Automated summary

The 0.3Mn/Ce8Si2Ox-R catalyst with a Ce/Si ratio of 8/2 showed superior performance at low temperatures, exhibiting high NOx conversion by increasing surface acidity and inhibiting the side reaction of NH3, leading to the highest NOx conversion and Fast-SCR process. Additionally, the catalyst displayed higher poison resistance to HCl compared to SO2 during catalytic activity suppression.