Effect of iron impurities on the catalytic activity of BEA, MOR and MFI zeoli…

Abstract. The combined use of chemical analysis, XRD, EPR and Mossbauer techniques provides detailed information on the nature of iron impurities in commercial BEA, MOR and MFI zeolites. EPR and Mo¨ ssbauer spectroscopies evidence that iron impurities are present mainly as tetrahedral Fe(III) species and to a minor extent as octahedral Fe(III) species, with relative amounts depending on th…