Promotion effects of SiO2 or/and Al2O3 doped CeO2/TiO2 catalysts for selective catalytic reduction of NO by NH3

Abstract A series of the CeO 2 -based catalysts loaded on TiO 2 , TiO 2 –SiO 2 , TiO 2 –Al 2 O 3 , and TiO 2 –SiO 2 –Al 2 O 3 supports were prepared by incipient impregnation method for the selective catalytic reduction (SCR) of NO by NH 3 in the presence of oxygen. The SCR activities of the catalysts with different supports increases in the order of Ce/TiO 2 2 –20SiO 2  ≈ Ce/TiO 2 –3.5Al 2 O 3 2 –20SiO 2 –3.5Al 2 O 3 . The Ce/TiO 2 –20SiO 2 –3.5Al 2 O 3 catalyst showed 100% NO conversion in the temperature range of 250–425 °C and 100% N 2 selectivity in the whole temperature range. The catalytic activity of Ce/TiO 2 –20SiO 2 –3.5Al 2 O 3 exhibited good stability and strong resistance to SO 2 and H 2 O poisoning. The co-introduction of SiO 2 and Al 2 O 3 into TiO 2 could increase the amount of chemisorbed oxygen and Lewis acid sites on the surface of catalyst, which should be responsible for the excellent SCR activity.