Simultaneous Removal of NO_x and PM over La_<i>1-x</i>K_<i>x</i>Co_<i>1-y</i>Mn_<i>y</i>O₃ Perovskite-Type Catalysts

Abstract

To study the effect of K and Mn substitution on simultaneous removal of NOx and particulate materials (PM), a series of La1-xKxCo1-yMnyO3 (x, y=0.1, 0.2, 0.3, 0.4, 0.5) perovskite-type catalysts were synthesized by complex-combustion method. The catalytic performances of the catalysts were evaluated by temperature-programmed oxidation reaction (TPO). And the catalysts were characterized by XRD, FT-IR, H2-TPR techniques. After introducing K and Mn to LaCoO3 simultaneously, all the samples possess perovskite-type structures and the B-site ions form higher average oxidation state enhancing the catalytic performance obviously. La0.8K0.2Co0.7Mn0.3O3 catalyst exhibits not only the lowest T i(297 °C) temperature but also the lowest Tm (343 °C) temperature. Meanwhile, the NO reduction percentage over this catalyst can reach 97%.