Insight into the combined catalytic removal properties of Pd modification V/TiO2 catalysts for the nitrogen oxides and benzene by: An experiment and DFT study

Abstract The effect of Pd on the combined catalytic removal properties of Vy/TiO2 for benzene and NOx has been investigated. It was found that the benzene conversion, NOx conversion and CO2 selectivity of Vy/TiO2 catalysts improved significantly after the modified by Pd at a space velocity (SV) of 12,000 mL·g−1·h−1, especially the Pd0.12V4/TiO2 catalyst. Accor ding to the characterization and calculation results, additional reaction active sites on anatase-TiO2 surfaces were provided after the addition of 1.2%Pd and facile redox cycle (2V4+ + Pd2+ ↔ 2V5+ +Pd0) can be explained for the excellent benzene and NOx catalytic performance of Pd0.12V4/TiO2 catalyst. The possible catalytic removal transformation mechanism of benzene and NOx by Pd0.12V4/TiO2 catalyst was proposed, respectively. Additionally, in the combined catalytic removal process of NOx and benzene, NO2 and NO may become the O-materials for benzene oxidation process over Pd0.12V4/TiO2 catalyst, and NOx is reduced to N2.