The reaction of NO + C3H6 + O2 over the mesoporous SBA-15 supported transition metal catalysts

摘要

A series of mono-functional M/SBA-15 (M = Cu, Fe, Cr, and Al) and bifunctional M'/SBA-15 (M' = Cu-Al, Fe-Al, and Cr-Al) catalysts was prepared via an incipient wetness impregnation, and further characterized by N2 adsorption, XRD, TEM, H2-TPR, Al~(27)-NMR, and XPS as well as activity test for C3H6 + NO + O2 reaction. Ordered mesoporous structure of SBA-15 was well maintained even after impregnating the various metallic components. The deNO_x activities of investigated catalysts follow a trend of Cu-Al/SBA-15 > Cu/SBA-15, Fe/SBA-15 > Cr-Al/SBA-15 > Cr/SBA-15 " Fe-Al/SBA-15, Al/SBA-15 > SBA-15. Synergistic effect between copper and alumina was achieved showing a satisfactory NO conversion of approximately 80% over Cu-Al/SBA-15 at temperature as low as 350℃ under an atmosphere of 3000 ppm NO, 3000 ppm C3H6, 1 % O2 and GHSV of 60,000 h~(-1). The SCR performance was found to be strongly correlated to the redox properties of tested catalysts, essentially chemical nature of supported metals, and surface density of active metallic species.