Copper(II)-Substituted Polyoxotungstates Immobilized on Amine-Functionalized SBA-15: Efficient Heterogeneous Catalysts for Liquid Phase Oxidative Reaction

The tricopper(II)-substituted polytungstates, [(Cu(H2O))(3)(alpha-XW9O33)(2)](12-) (Cu3X2W18, X = Bi-III, Sb-III), immobilized on (3-aminopropyl)triethoxysilane modified ordered mesoporous silica materials, Cu3X2W18 -NH2-SBA-15 were prepared, and the structures and properties of the catalysts were characterized by FT-IR, XRD, N-2 nitrogen adsorption/desorption measurements and TEM techniques. Results demonstrated that the heteropolyanions are highly dispersed on mesoporous materials. The resulting catalysts exhibited highly efficient catalytic activity for both the selective oxidation of benzyl alcohol to the benzaldehyde and the oxidation of thiophene with 30 % hydrogen peroxide as oxidant. Moreover, the catalysts could be recovered and reused five times without significant loss in their catalytic activity. [GRAPHICS] .