N sub(2)O decomposition over wet- and solid-exchanged Fe-ZSM-5 catalysts

The N sub(2)O decomposition activity of Fe-ZSM-5 strongly depends on the iron content and the preparation methods, including wet (WIE) and solid state ion exchanges (SSIE). The state of Fe species formed on the surface of a series of Fe-ZSM-5 catalysts containing a variety of Fe contents with respec...

Ausführliche Beschreibung

Gespeichert in:
Bibliographische Detailangaben
Veröffentlicht in:Applied catalysis. B, Environmental Environmental, 2008-02, Vol.78 (3-4), p.342-354
Hauptverfasser: Park, Joo-Hyoung, Choung, Jong-Hyun, Nam, In-Sik, Ham, Sung-Won
Format: Artikel
Sprache:eng
Schlagworte:
Online-Zugang:Volltext
Tags: Tag hinzufügen
Keine Tags, Fügen Sie den ersten Tag hinzu!
Beschreibung
Zusammenfassung:The N sub(2)O decomposition activity of Fe-ZSM-5 strongly depends on the iron content and the preparation methods, including wet (WIE) and solid state ion exchanges (SSIE). The state of Fe species formed on the surface of a series of Fe-ZSM-5 catalysts containing a variety of Fe contents with respect to the preparation method and their role for N sub(2)O decomposition activity have been systematically examined. The general trend for the decomposition activity of Fe-ZSM-5-SSIE is higher than that of Fe-ZSM-5-WIE, indicating the formation of a distinctive local structure of Fe on the catalyst surface during the course of the ion-exchange procedure. Based upon the Fourier transformed Fe K-edge EXAFS spectra for the series of Fe-ZSM-5-SSIE and -WIE catalysts, most of the Fe species on the surface of Fe-ZSM-5-SSIE with high Fe loading are well dispersed in the form of oxygen-bridged binuclear Fe species. The turnover frequency (TOF) for N sub(2)O decomposition under dry and wet conditions has been confirmed assuming that Fe-ZSM-5-SSIE samples with Fe/Al = 0.20 and Fe/Al = 0.65 only contain mononuclear and binuclear Fe species, respectively, as active reaction species on their surface. The high performance of Fe-ZSM-5-SSIE may be mainly due to the formation of the binuclear Fe species onto its surface during the preparation of the catalyst.
ISSN:0926-3373
DOI:10.1016/j.apcatb.2007.09.020