Low temperature selective catalytic reduction of NOx by NH3 over Cu modified V2O5/TiO2–carbon nanotube catalyst

A set of CuO–V2O5/TiO2–carbon nanotubes catalysts were prepared by sol–gel method and the structural characteristics of the prepared catalyst were examined by scanning electron microscope, Fourier transform infrared spectroscopy, Brunauer–Emmett–Teller surface area measurements, X-ray diffraction, X-ray photoelectron spectroscopy and temperature programmed desorption (TPD) analyses. It was observed from the results that vanadium particles were highly dispersed on the CNTs wall and the promotional effects of CuO over V2O5/TiO2–CNTs catalyst were also investigated. The positivity of the catalytic activity was attributed to the diameter of the CNTs used. Among the catalysts, V–Cu1/Ti–C10 (1 wt% Cu & 10 wt% CNTs) with CNTs having an outer diameter of 10–15 nm attained a NOx removal efficiency of 94% at 300 °C under a gas hourly space velocity of 30,000 h−1. The existence of copper species in the form of small CuO clusters and Cu2+ ions in the catalyst enhanced the redox properties of the catalyst. The presence of CNTs improved catalytic activity and provides better resistance to SO2 and H2O at the low reaction temperatures.