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To provide insight into optimizing flue gas treatment, simultaneous removal of elemental mercury (Hg0) and NO using a CeO2modified V2O5–WO3/TiO2catalyst was investigated. The results show that a novel V2O5–WO3/TiO2–CeO2catalyst exhibits excellent Hg0oxidation efficiency (88%) and NO conversion efficiency (89%) at 250 °C. Furthermore, CeO2modified V2O5–WO3/TiO2not only exhibits enhanced catalytic activity but also good resistance in SO2and H2O. These catalysts were also characterized using BET, SEM, XRD, XPS, and H2-TPR. We found lower crystallinity, more reduced species and better texture properties to be presented, which were all ascribed to CeO2doping. Also, the redox cycle (V4++ Ce4+↔ V5++ Ce3+) plays a key role in promoting Hg0oxidation and NO conversion. In tune with the experimental results, a mechanism for the simultaneous removal of Hg0and NO was proposed for the V2O5–WO3/TiO2–CeO2catalysts.

Removing NOxby supported catalysts is important for industrial flue gases and exhaust fumes of diesel engines at low temperature (100–300 °C). However, it is still a challenge to develop the low-temperature catalyst (LTC) for selective catalytic reduction of NOx, especially at temperatures below 200 °C. This paper reviews the effect of the different carriers with different active centres. Most supported metal oxide catalysts are prepared by impregnation method. But under the same condition, catalysts perform better if they were prepared by sol–gel method. Also, this paper described and compared the research progress of reaction mechanism and kinetics of the supported catalysts which were used for the selective catalytic reduction of NOxat low temperature. There are different mechanisms because of the different reducing agents and active centres. The L–H and E–R mechanisms, or both of them coexisting, can explain the overall mechanism. In order to research the mechanism thoroughly, the exploration of the reactions of the surface chemical process may be a direction to develop low temperature supported catalysts for removing NOx.