The Ce doping Cu/ZSM-5 as a new superior catalyst to remove NO from diesel engine exhaust

Abstract The Ce doping Cu/ZSM-5 catalysts were prepared using an improved incipient-wetness-impregnation method, and their catalytic performances were tested for the selective catalytic reduction (SCR) of NO with NH 3 . The aim of the present study was to understand and elucidate the deNO x activity as well as deactivation behaviors of the Ce doping Cu/ZSM-5 catalyst. The catalysts were characterized by a series of analytical techniques, including XRD, NH 3 -TPD, TEM, XPS, and TGA. The results indicated that the well dispersion of CuO nanoparticles was the primary cause for the high deNO x performance of the Ce doping Cu/ZSM-5 catalyst. The addition of Ce greatly improved the hydrothermal stability of the Cu/ZSM-5 catalyst, due to it could stabilize the dispersion of CuO and suppress the bulk-type CuO crystallites formation during hydrothermal treatment. The inhibition of deposition of CuSO 4 by doping of Ce made the Cu/ZSM-5 catalyst a good resistance to SO 2 . In conclusion, the catalytic performance, hydrothermal stability and SO 2 resistance of the Cu/ZSM-5 catalyst were greatly improved by the addition of Ce, which made the Ce doping Cu/ZSM-5 as a promising catalyst for the NH 3 -SCR technology.