Characterization and activity of Fe-ZSM-5 catalysts for the total oxidation of phenol in aqueous solutions

Fe-ZSM-5 zeolites with of Si/Fe ratios varying from 40 to 200 were synthesi zed and characterized by IR, XRD, SEM, ESR and ion-exchange techniques. Fro m the obtained results, it is possible to conclude that, these zeolites hav e a good crystallinity and that the incorporation of Fe3+ ions into the MFI -structure depends on the Si/Fe ratios in the gel: the higher the Si/Fe rat io, the more the percentage of Fe3+ ions is incorporated into the MFI latti ce. Catalytic properties of Fe-ZSM-5 were studied in the oxidation of phenol. T he reaction was performed in a static system, at the atmospheric pressure, 343 K, and with H2O2 concentration, which exceeds stoichiometric concentrat ion for complete oxidation of phenol to carbon dioxide and water. From the catalytic results, it can be concluded that framework Fe can catalyze more completely phenol oxidation than the extra-framework Fe does. (C) 2001 Else vier Science B.V. All rights reserved.