In situ DRIFTS FT-IR and DFT study on Fe-V-W/Ti removal of NO and VOCs.

Nitrogen oxides (NO) and volatile organic compounds (VOCs) are generated during the coal-fired power plant's combustion. They can be simultaneously removed in SCR (selective catalytic reduction) region. Herein, the performance of V-W/Ti and Fe-V-W/Ti synthesized by wet impregnation in removing NO and VOCs was evaluated. XPS (X-ray photoelectron spectroscopy) result indicated that a redox cycle of Fe  + V  ⇌ Fe  + V could form electron vacancy through electron transfer. Besides, the mechanisms of NH-SCR and VOCs catalytic oxidation were explored with in situ DRIFTS experience and DFT calculation. On Fe-V-W/Ti, in situ DRIFTS study found more absorption sites of NH, and different intermediates during simultaneously removal process. DFT calculation demonstrated that absorption energy of O was decreased and O = O bond was lengthened with Fe doped. Both V-W/Ti and Fe-V-W/Ti followed the L-H mechanism and shared a common NH-SCR pathway: [Formula: see text]. However, the bidentate nitrate and monodentate nitrate were also revealed on Fe-V-W/Ti, which combined with NH and decomposed into N and HO, or NO and HO, respectively. The detected NH species combined with NO on the Fe-V-W/Ti, following the E-R mechanism. As for VOCs, the intermediates of benzene and toluene were revealed by in situ DRIFTS study, and detailed Mars-van Krevelen mechanism was discovered.