Effect Ofmesoporous Supports on Gold Nanoparticles Activity in Toluene Oxidation

Gold nanoparticles supported over mesoporous ceria (Au/CeO₂), titania (Au/TiO₂) and iron oxide (Au/Fe₂O₃) were prepared by deposition-precipitation with urea and used for toluene oxidation. The mesoporous CeO₂, Fe₂O₃, andTiO₂ were synthesized employing a hard-template approach using SBA-15 as the template. The catalysts were characterized by BET, X-ray diffraction (XRD), H₂-temperature programmed reduction (H₂-TPR), diffuse reflectance UV-Vis spectroscopy (DR/UV-Vis), and high-resolution transmission electron microscopy (HRTEM). Based on the temperature required to achieve 50% toluene conversion in the oxidation reaction (T_50%), the activity sequence was Au/CeO₂ > Au/Fe₂O₃ > Au/TiO₂. The Au/CeO₂ catalyst was the most active catalyst, achieving 50% toluene conversion at 240°C and full toluene conversion at 295°C demonstrating high stability over successive catalytic runs.