Effect of vanadium and tungsten loading order on the denitration performance of F-doped V2O5-WO3/TiO2 catalysts.

F-doped V₂O₅-WO₃/TiO₂ catalyst has been confirmed to have excellent denitration activity at low temperatures. Since the V₂O₅-WO₃/TiO₂ catalyst is a structure-sensitive catalyst, the loading order of V₂O₅ and WO₃ may affect its denitration performance. In this paper, a series of F-doped V₂O₅-WO₃/TiO₂ catalysts with different V₂O₅ and WO₃ loading orders were synthesized to investigate the effect of denitration performance at low temperatures. It was found that the loading orders led to significant gaps in denitration performance in the range of 120–240 °C. The results indicated loading WO₃ first better utilized the oxygen vacancies on the TiF carrier promoting the generation of reduced vanadium species. In addition, loading WO₃ first facilitated the dispersion of V₂O₅ thus enhanced the NH₃ adsorption capacity of VWTiF. In situ DRIFT verified the rapid reaction between NO₂, nitrate, and nitrite species and adsorbed NH₃ over the VWTiF, confirming that the NH₃ selective catalytic reduction (NH₃-SCR) reaction over VWTiF at 240 °C proceeded by the Langmuir-Hinshelwood (L-H) mechanism. This research established the constitutive relationship between the loading order of V₂O₅ and WO₃ and the denitration performance of the F-doped VWTi catalyst providing insights into the catalyst design process. [ABSTRACT FROM AUTHOR]