Collect. Czech. Chem. Commun.
2002, 67, 1743-1759
https://doi.org/10.1135/cccc20021743
Study of the Influence of Water on Oxidative Properties of Fe3+ in ZSM-5 Zeolite Channels
Gabriel Číka,*, Milada Hubinováa, František Šeršeňb and Vlasta Brezovác
a Department of Environmental Engineering, Faculty of Chemical and Food Technology, Slovak University of Technology, 812 37 Bratislava, Slovak Republic
b Institute of Chemistry, Faculty of Natural Science, Comenius University, 842 15 Bratislava, Slovak Republic
c Department of Physical Chemistry, Faculty of Chemical and Food Technology, Slovak University of Technology, 812 37 Bratislava, Slovak Republic
Abstract
The interactions of phenol and thiophene with Fe3+ ions have been studied in ZSM-5 zeolite channels in the presence of water. The Fe-ZSM-5 was prepared by the ion exchange of Fe3+ for Na+. The Fe3+ ions in zeolite channels have unsaturated co-ordination spheres and oxidize organic substrates (phenol, thiophene) at room temperature. The interaction of Fe3+ with phenol gives rise to the stabilized cation-radical PhOH•+ and thiophene forms low oligomers (2-6 monomeric units). The oligomers are present in the neutral as well as oxidized form as cation-radicals (polarons). The formation of dications (bipolarons) has not been observed.
Keywords: Aluminosilicates; Zeolites; Molecular sieves; Heterogeneous catalysis; Transition metals; Cation-radicals; Oxidation; Phenol; Thiophene.
References: 42 live references.
