WO₃ Nanoparticles on MCM-48 for the Oxidation of Olefins

Significance

WO₃ nanoparticles supported on MCM-48 were found to work as highly efficient catalysts for the oxidation of olefins. Nanoparticles (WO₃/MCM-48) with an average size of 2-3 nm were obtained in three steps (WCl₆+MCM-48; Δ 300 °C, H₂ then O₂). These nanoparticles exhibited high activity (99% yield) for the epoxidation of cyclooctene using 50% aqueous H₂O₂, whereas larger particles (3-10 nm) showed moderate activity (78% yield). WO₃ supported on alumina, TiO₂, active carbon, CeO₂, MgO, and Montmorillonite K 10 also gave low activity (10-79% yield). Moreover, nanoparticles (WO₃/MCM-48) were readily recovered by filtration and reused up to five times without loss of any activity.