The monolithic cordierite supported V2O5-MoO3/TiO2 catalyst for NH3-SCR

The TiO2-nano sol was used to modify and construct the surface texture of cordierite honeycomb ceramic (CC). By varying the proportion and concentration of active components, a series of monolithic cordierite supported V2O5-MoO3/TiO2 catalysts were synthesized through impregnation method. The texture characteristics and the active components distribution of the obtained catalysts were investigated by Brun auer-Emmett-Teller (BET), Raman, H-2-temperature programmed reduction (H-2-TPR) and X-ray photoelectron spectroscopy (XPS). The catalytic performances were evaluated by the NO conversion in the selective catalytic reduction (SCR) process. The dispersion of V-O-V on TiO2 support getting improved as increasing the Mo/V ratio, leading to the negative shift of XPS peaks for V 2p(1/2) and V 2p(3/2), while the positive shift for Ti 2p(1/2) and Ti 2p(3/2). Oppositely, elevating the loading amount of active species (VOx-MoOx) with a constant Mo/V ratio led to the crystallization of vanadium oxide, which would weakened the interaction force among active components and TiO2 support, and went against the catalytic activity and redox properties. All the samples exhibited excellent catalytic performances as well as the mechanical strength and washcoating stability. Especially, the V-0.9-Mo-7.2/Ti/CC catalyst with the Mo/V ratio of 8 exhibited the highest catalytic activity with NO conversion closing to 100%, with the SO2 and H2O durability exceeding 90% in the temperature range of 350-450 degrees C. (C) 2016 Elsevier B.V. All tights reserved.