Naphthalene total oxidation over metal oxide catalysts

Metal oxide catalysts (CoOx, MnOx, CuO, ZnO, Fe2O3, CeO2, TiO2, Al2O3 and CuZnO) prepared by a precipitation method have been characterised and tested for the total oxidation of naphthalene. The most effective catalyst for naphthalene oxidation was CeO2 prepared by a homogeneous precipitation method with urea. Moreover, the cerium oxide catalyst showed stable conversion with 100% selectivity to CO2 with time-on-stream at very low temperatures, 175 °C. The total oxidation of propane was also probed using the same range of catalysts and no correlation between naphthalene and alkane oxidation was apparent, indicating that different mechanisms are involved. It was observed that whilst redox properties were the main factor controlling propane total oxidation, the surface area and the strength of the bond between adsorbed molecules and catalyst surface were also important parameters affecting naphthalene catalytic combustion.