Fe/Beta@SBA-15 Core-Shell Catalyst: Interface Stable Effect and Propene Poisoning Resistance for NO Abatement

A series of Fe/Beta@SBA-15 core-shell structural catalysts were designed and controllablly constructed by an ultradilute liquid-phase coating method. Their catalytic activities were examined for ammonia selective catalytic reduction of NOx. It was found that their acidity and redox property were strongly dependent on SBA-15 shells, Fe/Beta@SBA-15 catalysts exhibit good propene and SO2 poisoning resistance, excellent hydrothermal stability, and wide NOx conversion temperature range (325-600 degrees C) under a high gas hour space velocity. The kinetics results indicate that the mesoporous structure of SBA-15 shell lowers the diffusion limitation and promotes the reactants accessing to active sites. Moreover, TGA and in situ DRIFT results reveal that SBA-15 shell can not only prevent the generation and deposition of coke and nitrate species from blocking active sites but also serve as an effective obstacle to inhibit active FeOx nanoparticles from agglomerating at high temperature, leading to the higher propene resistance than Fe/Beta. (C) 2018 American Institute of Chemical Engineers