Ni,Pt function in catalyst for diesel particulate removal from exhaust gases
The catalytic oxidation traps of particulate matter(PM) from diesel exhaust gases seem to be one of the best ways because of their simplicity, easy handing, high abatement efficiency and comparatively low cost.The development of catalysts for catalytic oxidation traps is presented. By using monolithic cordierite honeycomb as support which was modified by TiO_ 2,γ-Al_2O_3,Cu-K-V,catalyst was prepared by the impregnation method and modified by Ni and Pt. The catalyst was aged in a muffle oven in air for 3 h at 700℃ and characterized by BET, TG-IR and activity tested through DSC/TG experiments.The particulate matter combustion temperature at the highest oxidation reaction rate could be lowered remarkably,especially for removing graphitic solid fraction(GSF) in particulate matter.The catalytic performance was improved by adding Ni and Pt. For the aged catalysts modified by Pt, their activity decreased, in contrast, for the ones modified by Ni, their activity increased. The reason could be the migration of Ni from inner layer to catalyst surface during the aging process.