R. Monaci et al., Oxidative dehydrogenation of propane over V2O5/TiO2/SiO2 catalysts obtained by grafting titanium and vanadium alkoxides on silica, APP CATAL A, 214(2), 2001, pp. 203-212
Oxidative dehydrogenation of propane on V2O5/TiO2/SiO2 catalysts, prepared
by grafting, was investigated in the temperature range 673-773 K. The prepa
red samples were characterised by X-ray diffraction (XRD), Fourier-transfor
m infrared spectroscopy (FTIR), UV-VIS diffuse reflectance (DR UV-VIS), tem
perature programmed reduction (TPR) and Oz chemisorption. Crystalline V2O5
was not revealed on any sample, although the dispersion of the surface spec
ies steeply decreased with increasing vanadium loading. Non-isolated tetrah
edral V5+ were present on the surface at any vanadium concentration. In the
case of A(5) catalyst, the presence of octahedral vanadium species was als
o observed. (C) 2001 Elsevier Science B.V. All rights reserved.