Catalytic oxidation of ethanol and acetaldehyde over Pd/γ-Al_2O_3-TiO_2 catalysts

Pd/γ-Al2O3-TiO2 catalysts with 1% palladium loading were prepared by mixed sol-gel and mechanic mixing methods.Their activity for complete oxidation of ethanol and acetaldehyde was tested.The results showed that Pd/γ-Al2O3-TiO2 catalyst prepared by mixed sol-gel method is more active than Pd/TiO2 and Pd/Al2O3 separately for simultaneously oxidation of ethanol and acetaldehyde.The conversions of ethanol and acetaldehyde over Pd/γ-Al2O3-TiO2 at 150℃ were 98.9% and 98.5%,respectively;the catalyst also shows a good stability under these conditions.The bulk phase and surface characterizations like XRD,SEM and FT-IR showed that there may be a strong interaction between γ-Al2O3 and TiO2 on Pd/γ-Al2O3-TiO2,which brings on a moderate specific surface area and pore volume.γ-Al2O3 may take part in the formation of catalyst surface structure,which may be favorable for the catalytic oxidation of ethanol and acetaldehyde.