Phenol degradation and photodegradatio-n using O3/UV by Fe2O3 supported on Al2O3 and TiO2 prepared by sol-gel method

Different series of iron supported catalysts containing 10wt.% of iron, as oxide, on TiO2 and Al2O3 have been prepared by the sol gel method and the traditional method based on the impregnation of the support with the metal precursor on commercial and sol-gel supports. The calcined solids were characterised by evaluating the specific surface area and porosity by nitrogen adsorption at 77 K, TPR, TPD of ammonia, X-ray diffraction, evaluation of band gap and isolelectric point by electrophoretic migration. Fe3+ ions in two situations were found, highly dispersed in which Fe3+ ions were placed in the network of the support and large Fe2O3 Crystals were located on the surface catalysts. The catalytic activity of the prepared catalysts was measured in a batch reactor using ozone/UV as oxidizing agent. The catalysts displayed significant differences in initial reaction rate being the iron titania systems more active, specially when a higher extent of surface iron oxide species is present. After two hours on stream the conversion levels are similar in all the studied systems.