Formation of radicals and catalytic activity of H-ZSM-5-type zeolites in unsaturated hydrocarbon conversions: Part 2. Radical formation upon adsorption of aromatic compounds

• Published in: Journal of molecular catalysis Vol. 37; no. 1; pp. 107 - 115
• Main Authors: Kucherov, A.V., Slinkin, A.A., Kondratyev, D.A., Bondarenko, T.N., Rubinstein, A.M., Minachev, Kh.M.
• Format: Journal Article
• Language: English
• Published: Elsevier B.V 1986
• ISSN: 0304-5102
• DOI: 10.1016/0304-5102(86)85141-0

The formation of cation radicals upon adsorption of different aromatic compounds at 20–250 °C on H-ZSM-5 zeolites has been studied. It is shown that the concentration of the strong radical-forming sites in H-ZSM-5 (per Al 3+ ion of lattice) is not lower than that in H-mordenite. The selective blocking of external sites by 2,4,6-trimethylpyridine does not prevent the formation of benzene or p-xylene radicals, i.e. the majority of aromatic radicals formed are located inside the H-ZSM-5 channels. In the case of large molecules, some peculiarities of radical formation due to steric hindrance have been observed. The role of chemisorbed oxygen in the processes of aromatic cation radical formation on H-ZSM-5 and H-mordenite is discussed.