engleski

Mesoporous copper modified cerium oxide catalysts for toluene oxidation

Ceria (CeO2) is widely applied in catalysis due to its ability to store and release oxygen from its crystal lattice, as well as other advantages such as low price, resistance to poisoning and thermal stability. It is known that ceria exhibits good catalytic activity in the oxidation of volatile organic compounds (VOCs), which pose a great threat to both the environment and human health. Therefore, the aim of this work was to synthesize high surface area ceria-based nanocatalysts with high activity for the oxidation of toluene, which was chosen as a model VOC. Samples of pure CeO2 and CeO2 modified with 10 and 20 mol. % of Cu were synthesized via hard templating, i.e. nanocasting method using previously prepared KIT-6 mesoporous silica as the hard template, leading to a well- defined ordered mesoporous structure that favorably affects the catalytic properties. The prepared materials were characterized using powder X-ray diffraction and nitrogen physisorption. The XRD patterns indicate the presence of nanocrystalline ceria in all the prepared samples, while the obtained specific surface areas are quite high, between 130 and 160 m2 g-1. Pore size distributions are wide and in the mesopore range (4 to 30 nm). The mesoporous catalysts were tested for toluene oxidation process and all show great catalytic activity, reaching maximum toluene conversion between 250 and 280 °C. It can be concluded that the addition of copper increases the specific surface area and narrows the pore size distribution of prepared ceria catalyst, but it does not significantly affect the catalytic activity.

ceria ; copper ; mixed metal oxides ; nanostructure ; nanocasting, environmental catalysis

nije evidentirano