Catalytic performance of the Pd/TiO2 modified with MnOx catalyst for acetone total oxidation

Abstract

The key component of the catalytic oxidation technology is regarded to develop a stable and high activity catalyst. Herein, a series of PdMn/Ti catalysts have been prepared to oxidize acetone. By controlling the Mn amount, Pd dispersion on TiO2 has been adjusted, which has been confirmed by X-ray diffraction (XRD) and transmission electron microscopy (TEM). The X-ray photoelectron spectroscopy (XPS) results show that catalysts possessed more adsorbed oxygen content and an increasing proportion of palladium oxides after introducing manganese with multivalent states. Hydrogen-temperature programmed reduction (H2-TPR) shows that the introduction of Mn has improved the low temperature reducibility of the catalyst. Catalytic activities of catalysts with manganese are much higher than that of their counterparts without manganese. Among the prepared catalysts, the Pd0.01Mn0.2/Ti catalyst exhibited the excellent catalytic activity toward acetone oxidation. The T95 of acetone is 259 °C under the conditions of 1000 ppm of acetone concentration and 30,000 mL/(g h) of WHSV. The high catalytically activity of the Pd0.01Mn0.2/Ti catalyst could be ascribed to its good low temperature reducibility and abundant adsorbed oxygen and palladium oxides content. In addition, high valence states of Mn also contributed to the good catalytic activity of the Pd0.01Mn0.2/Ti catalyst.