Zeolite ferrous-exchanged

Further studies of ferrous-exchanged zeolite A with different degrees of hydrolysis (i.e. H+ content of the unit cell) indicated that the area under the outer doublet foimd in samples on dehydration (see Fig. 4b,c) was closely correlated to the degree of hydrolysis [13]. This outer doublet would seem to be associated with Fe ions contained in collapsed framework material. 

Iron salts or iron exchanged MMT deactivate H2O2 with the generation of O2, and show low alkane oxidation activity (< 0.5%). Complexation of iron by organic ligands has very specific effects on the spin state (II, III) and its electrophilicity and allows non-Fenton-type chemistry [13,14]. Mononuclear ferrous N,N -bis(2-pyridinecarboxamide)-l,2/3-R complexes in Na-Y zeolite (with R= alkane or benzene) are oxo-type catalysts [13]. Here a different reactivity pattern is expected for the dinuclear ferric complexes [14]. 

The synthesis procedure of ferrous-cyanide complexes in the zeolite Y was adopted from earlier studies [8,9]. Generally, the method involes the treatment of a ferrous ion exchanged NaY zeolite with methanolic solutions of cyanide. 

Rees LVC. Mossbauer spectroscopic studies of ferrous ion exchange in zeolite A. In Jacobs PA, Jaeger NI, Jim P, Schulz-Ekloff G, eds. Metal Microstructures in Zeolites. Preparation—Properties—Applications. Proceedings of a Workshop, Bremen, September 22-24, 1982. New York Elsevier Scientific, 1982 55-59. 

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