Enhanced low-temperature NH3-SCR performance of CeTiO catalyst via surface Mo modification

Abstract The effect of molybdenum oxide on the activity and durability of CeO2-TiO2 catalyst for NO reduction by NH3 was examined. It was found that the introduction of Mo could improve the low-temperature NH3-SCR activity and SO2/H2O durability of the CeO2-TiO2 catalyst and an optimal loading of Mo was 4 wt.%. The best MoO3/CeO2-TiO2 catalyst displayed over 90% NO conversion from 200°C to 400°C and obtained 4-fold increase in NO conversion compared to CeO2-TiO2 at 150°C. The characterization results revealed that the number of Bronsted acid sites over MoO3/CeO2-TiO2 was significantly increased, and the adsorption of nitrate species was dramatically weakened because of the coverage of MoO3, which were favorable for the high NH3-SCR performance. It is believed that the MoO3/CeO2-TiO2 catalyst is a suitable substitute for the NH3-SCR reaction.