Catalytic removal of NO2 by nickel-platinum catalyst supported on multi-wall carbon nanotubes

In the present study, the NO2 removal efficiency at concentrations of 3000 to 5000 ppm was evaluated by nickel and platinum bimetallic catalyst supported on multiwalled carbon nanotubes (Ni-Pt/MWCNT) along with water vapor at different space velocity and temperatures. Morphological and structural characteristics, material formation phases and catalyst regeneration were investigated by FE-SEM, XRD and TPR tests, respectively. The results showed that increasing the weight percentage of platinum at Ni-Pt/MWCNT catalyst improved the removal efficiency at low temperature. The catalyst 25%W.Ni-3%W.Pt/MWCNT provided 92% removal efficiency at the temperature of 300 degrees C, space velocity of 25000/hr and concentration of 3000 ppm, while, the 15%W.Ni-5%W.Pt/MWCNT represented highest removal efficiency (70%) at the temperature of 150 degrees C. The removal efficiency of Ni-Pt/MWCNT catalyst is affected by the weight percentage of nickel and platinum, as well as the NO2 concentration at various temperatures. The results suggest that H2O can be used as a reducing agent to reduce NO2 by produced H+. The 25%W.Ni-3%W.Pt/MWCNT catalyst removal efficiency at the vicinity of water vapor and concentration of 3000 ppm NO2, unchanged stability over the period of 100 minute.