Liquid-phase aerobic oxidation of benzyl alcohol catalyzed by Pt/ZrO2

Abstract

The oxidation of benzyl alcohol by molecular oxygen in the liquid phase and catalyzed by Pt/ZrO2 using n-heptane as the solvent was studied. Pt/ ZrO2 was very active and 100 % selective for benzyl alcohol conversion to benzaldehyde. The catalyst can be separated by filtration and reused. No leaching of Pt or Zr into the solution was observed. Typical batch reactor kinetic data were obtained and fitted to the Langmuir-Hinshelwood, Eley-Rideal and Mars-van Krevelen models of heterogeneously catalyzed reactions. The Langmuir-Hinshelwood model was found to give a better fit. The rate-determining step was proposed to involve direct interaction of an adsorbed oxidizing species with the adsorbed reactant or an intermediate product of the reactant. H2O2 was also proposed to be an intermediate product. n-Heptane was found to be an appropriate solvent in this reaction system. © 2007 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.