The system Fe2O3/MCM-41, with high iron dispersion, was synthesized in order to introduce Lewis acid sites into the MCM-41 structure. Two calcination atmospheres (inert and oxidant) were used to produce iron nanoclusters with different structural properties. Besides, a silylation treatment was realized on both solids with the aim of neutralizing the Bronsted acidity associated with the MCM-41 silanol groups. The samples were characterized by atomic absorption spectroscopy, X-ray diffraction at low angles, N-2 adsorption, temperature-programmed reduction, Fourier transform infrared spectroscopy, nuclear magnetic resonance of Si-29, and Mossbauer spectroscopy. The influence of the structural changes of the nanoclusters and the effect of the simultaneous presence of Lewis and Bronsted acid sites were evaluated studying the product distribution from the alpha-pinene oxide isomerization reaction. It was determined that the Bronsted acidity of the Fe/MCM-41 system has not the sufficient acid strength to modify the product distribution which is mainly governed by the Lewis sites.
Influence of the Brönsted and Lewis acid sites on the catalytic activity and selectivity of Fe/MCM-41 system / N.A. Fellenz, J.F. Bengoa, S.G. Marchetti, A. Gervasini. - In: APPLIED CATALYSIS A: GENERAL. - ISSN 0926-860X. - 435(2012 Sep 05), pp. 187-196.
|Titolo:||Influence of the Brönsted and Lewis acid sites on the catalytic activity and selectivity of Fe/MCM-41 system|
GERVASINI, ANTONELLA (Ultimo)
|Parole Chiave:||POX isomerization ; Lewis acid sites ; MCM-41 ; Mossbauer spectroscopy|
|Settore Scientifico Disciplinare:||Settore CHIM/02 - Chimica Fisica|
|Data di pubblicazione:||5-set-2012|
|Digital Object Identifier (DOI):||http://dx.doi.org/10.1016/j.apcata.2012.06.003|
|Appare nelle tipologie:||01 - Articolo su periodico|