1 Department of Chemistry, Technical University of Denmark2 Centre for Catalysis and Sustainable Chemistry, Department of Chemistry, Technical University of Denmark3 Department of Chemical and Biochemical Engineering, Technical University of Denmark4 CHEC Research Centre, Department of Chemical and Biochemical Engineering, Technical University of Denmark5 Center for Electron Nanoscopy, Technical University of Denmark6 Center for Hyperpolarization in Magnetic Resonance, Center, Technical University of Denmark
V2O5–WO3/TiO2 catalysts were prepared by incipient wetness impregnation and deposition–precipitation (DP) methods. The catalysts were characterized by N2 physisorption, X-ray powder diffraction, Fourier transform infra red spectroscopy, electron paramagnetic resonance spectroscopy, transmission electron microscopy, H2-temperature programmed reduction and NH3-temperature programmed desorption. The catalysts exhibited only crystalline TiO2 phases with the active metal and promoter in highly dispersed or amorphous state. The 3 wt% V2O5–10 wt% WO3/TiO2 catalyst prepared by DP using ammonium carbamate as a precipitating agent was found to be the most active and selective to N2. The superior activity of the catalyst can be ascribed to the altered acidic and redox properties of vanadium. The catalysts did not show increased potassium resistance with the change in preparation method or with increasing vanadium concentration. Furthermore, potassium-poisoned catalysts showed above stoichiometric loss of surface acidity. Thus, these modified formulations are suggested to be used in coal/natural gas-fired power plants where there is a demand for high selective catalytic reduction activity and selectivity to N2.
Journal of Materials Science, 2014, Vol 49, Issue 7, p. 2705-2713