Simultaneous removal of elemental mercury and NO from simulated flue gas using a CeO2 modified V2O5–WO3/TiO2 catalyst

To provide insight into optimizing flue gas treatment, simultaneous removal of elemental mercury (Hg0) and NO using a CeO2 modified V2O5–WO3/TiO2 catalyst was investigated. The results show that a novel V2O5–WO3/TiO2–CeO2 catalyst exhibits excellent Hg0 oxidation efficiency (88%) and NO conversion efficiency (89%) at 250 °C. Furthermore, CeO2 modified V2O5–WO3/TiO2 not only exhibits enhanced catalytic activity but also good resistance in SO2 and 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 CeO2 doping. Also, the redox cycle (V4+ + Ce4+ ↔ V5+ + Ce3+) plays a key role in promoting Hg0 oxidation and NO conversion. In tune with the experimental results, a mechanism for the simultaneous removal of Hg0 and NO was proposed for the V2O5–WO3/TiO2–CeO2 catalysts.

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