6533b850fe1ef96bd12a818d
RESEARCH PRODUCT
M�ssbauer study of the spatial distribution of the active species in Cs doped Fe2O3-V2O5 catalysts
W. MeiselH. MehnerA. Brücknersubject
chemistry.chemical_classificationDopantSulfideChemistryInorganic chemistryIron sulfideBiochemistryAnalytical ChemistryAmorphous solidlaw.inventionCatalysischemistry.chemical_compoundlawCalcinationCrystalliteSurface layerdescription
From a Cs doped Fe2O3-V2O5 (Fe:V=1.4) catalyst exhibiting an inhomogeneous composition after calcination, three different fractions have been separated by visual inspection. One fraction has been found to consist of mainly α-Fe2O3, another one of mainly FeVO4. The third fraction (S1 in the text) is the catalytically most active fraction containing besides both of the former components an amorphous phase of FexVyOz and also the dopant. By combining the results from transmission and conversion electron Mossbauer spectra it has been concluded that the amorphous component is enriched in the surface region of the crystallites of the catalyst. In addition, the formation of a thin surface layer of iron sulfide (Fe1−xS) on the third fraction has been identified. This sulfide is assumed to be formed during calcination from Cs2SO4 used for the preparation of the catalyst.
year | journal | country | edition | language |
---|---|---|---|---|
1995-01-01 | Fresenius' Journal of Analytical Chemistry |