Synthesis by sol-gel process, characterization and catalytic activity of vanadia-silica mixed oxides

This paper describes a new route for the preparation of V2O5-SiO2 mixed oxides with high vanadium content and high surface area by the sol-gel processing method. Dry samples were characterized by powder X-ray diffraction, electron paramagnetic resonance, Fourier-transform infrared, and energy dispersive X-ray spectrometry. Our results show that the incorporation of vanadium pentoxide into the silica matrix was obtained by intimate mixing of the two different inorganic polymers (Si-O and V-O based polymers), and the overall structure is held together by a Si-O-Si network interpenetrated with V-O-V polymeric chains. The catalytic activity of the V2O5-SiO2 mixed oxides was evaluated in the oxidation of the cyclooctene and styrene in liquid phase.