Simultaneous removal of NO and dichloromethane (CH2Cl2) over Nb-loaded cerium nanotubes catalyst.

Herein, a series of niobium oxide supported cerium nanotubes (CeNTs) catalysts with different loading amount of Nb2O5 (0-10 wt.%) were prepared and used for selective catalytic reduction of NOx with NH3 (NH3-SCR) in the presence of CH2Cl2. Commercial V2O5-WO3-TiO2 catalyst was also prepared for comparison. The physcial properties and chemical properties of the Nb2O5 loaded cerium nanotubes catalysts were investigated by X-ray diffractometer, Transmission electron microscope, Brunauer-Emmett-Teller specific surface area, H2-temperature programmed reduction, NH3-temperature programmed desorption and X-ray photoelectron spectroscopy. The experiment results showed that the loading amount of Nb2O5 had a significant effect on the catalytic performance of the catalysts. 10 wt.% Nb-CeNTs catalyst presented the best NH3-SCR performance and degradation efficiency of CH2Cl2 among the prepared catalysts, due to its superior redox capability, abundant surface oxygen species and acid sites, the interaction between Nb and Ce, higher ratio of Nb4+/(Nb5++ Nb4+) and Ce3+/(Ce3+ + Ce4+), as well as the special tubular structure of cerium nanotube. This study may provide a practical approach for the design and synthesis of SCR catalysts for the simultaneously removal NOx and chlorinated volatile organic compounds (CVOCs) emitted from the stationary industrial sources.