Structural modelling of coprecipitated VTiO catalysts

LAURA E. BRIAND; RITA D. BONETTO; MARIO A. SANCHEZ; HORACIO J. THOMAS

CATALYSIS TODAY

Elsevier

Lugar: Amsterdam; Año: 1996 vol. 32 p. 205 - 213

0920-5861

A statistical study of the particle shape and size of pure V2O5 and TiO2, and samples of coprecipitated V2O5---TiO2 catalysts with different V/Ti ratios, has been performed. They were also characterized by XRD, EDAX, SEM and XPS. The results showed that pure vanadium pentoxide is compose by large square or needle-shaped particles, while pure titanium dioxide has small and rounded ones. VTiO samples presented an area and shape, depending on the V/Ti ratio. These results and the spectroscopical characterization conducted to a particle model of the catalysts. Those VOTi samples with high V/Ti ratio would have large V2O5 crystals acting as support of a V/TiO2 solid solution. In contrast, those samples with a low V/Ti ratio, would have the solid solution supporting vanadium pentoxide crystals.