Plasma-assisted CuO/CeO2/TiO2-γ-Al2O3 catalysts for NO + CH4 reaction and NO temperature programmed desorption studies

The removal of NO and CH4 has been studied with a hybrid system integrating plasma activation and four Cu-based catalysts. The best catalytic performance was observed for catalysts obtained from CuO/CeO2/TiO2/gamma-Al2O3. The efficiency of NO removal decreased with the order: 12% CuO/10% CeO2/15% TiO2/gamma-Al2O3 > 12% CuO/15% TiO2/gamma-Al2O3 > 12% CuO/gamma-Al2O3 > 12% CuO/TiO2. Brunauer-Emmett-Teller (BET), X-ray diffraction (XRD) Temperature-programmed reduction (H-2-TPR) and NO temperature-programmed desorption (NO-TPD) experiments were carried out to gain insight into the synergetic effects with the catalysts. The results revealed that copper species existed as bulk CuO crystalline for all the catalysts, H-2-TPR suggested that the Cu2+ incorporated TiO2 or CeO2 lattice and crystalline CuO might be the most active component for NO removal, and NO-TPD studies indicated that 12% CuO/10% CeO2/15% TiO2/gamma-Al2O3 catalyst had lower NO desorption temperature and larger peak area, which seemed to be responsible for the better catalytic activity over NO + CH4 reactions than other catalysts. (C) 2013 Elsevier B.V. All rights reserved.