Highly selective oxidation of benzyl alcohol over Pt-sulphated zirconia supported on SBA-15 catalyst by using a high-pressure fixed bed reactor

An active platinum loaded sulphated zirconia supported SBA-15 catalyst (Pt/SO4/ZrO2-SBA-15) was synthesized and characterized using scanning electron microscope, transmission electron microscope, N2adsorption-desorptionisotherms. The different percentage level (10, 20 and 30 wt.%) of ZrO2 was loaded on SBA-15 by precipitation of zirconium oxychloride, calcined and sulfated with H2SO4. The sulphated zirconia supported SBA-15 catalyst were loaded with 0.5 wt.% of Pt and characterized by different characterization technique. The Pt-loaded catalysts were evaluated to the selective oxidation of benzyl alcohol to benzaldehyde by the continuous-flow reactor system. Also, the bulk sample of SO4-ZrO2 and Pt-SO4-ZrO2 was prepared for the comparison purposes. The supported catalysts, even at the lowest loading of 10% ZrO2were more active than unsupported SO4-ZrO2. The catalyst containing 20% of ZrO2 was most active for the selective oxidation of benzyl alcohol; the highest activity was obtained over this catalyst at a lower temperature (90 °C). The Pt/SZ-SBA-15 catalyst showed very high catalytic activity and selectivity to benzyl alcohol oxidation. Besides, the long-term stability of the Pt/SZ-SBA-15 catalyst was excellent and there is no loss in catalytic activity or selectivity occurred during the time of continuous operation.