Role of Iron Impurities in Formation of Electron-accepting Sites in H-ZSM-5 Zeolites : 15N Nuclear Magnetic Resonance and 15N Nuclear Magnetic Relaxation of Adsorbed N2 and N2O
Journal of the Chemical Society - Faraday Transactions (1990-1998, in 1999 become Physical Chemistry Chemical Physics)
||HETEROGENEOUS CATALYSTS; GAMMA-ALUMINA; ACID SITES; NMR; C-13; SPECTROSCOPY; MOLECULES; PYRIDINE; ZSM-5
Institute of Catalysis, Novosibirsk 630090, USSR
15 N NMR chemical shifts of N2 and N2O molecules as well as 15N relaxation rates of N2O adsorbed on a series of H-ZSM-5 zeolites, H-Y zeolite, SiO2 and γ-Al2O3 containing controlled quantities of iron impurities have been studied. Unlike the SiO2, γ-Al2O3 and H-Y samples, the H-ZSM-5 zeolites have strong electron-accepting sites formed by Fe3+ and probably Al3+ cations. The possible structure of acidic sites and the geometry of the complexes formed during N2O adsorption are discussed.