Contribution of Fe and Protonic Sites in Calcined and Steamed ZSM-5 Zeolites to Oxidation of Benzene with N2O to Phenol and Selective Catalytic Reduction of NO with Propane to Nitrogen

0181744 - UFCH-W 20030181 RIV CZ eng J - Journal Article
Čapek, Libor - Kubánek, Petr - Wichterlová, Blanka - Sobalík, Zdeněk
Contribution of Fe and Protonic Sites in Calcined and Steamed ZSM-5 Zeolites to Oxidation of Benzene with N2O to Phenol and Selective Catalytic Reduction of NO with Propane to Nitrogen.
Collection of Czechoslovak Chemical Communications. Roč. 68, č. 10 (2003), s. 1805-1818. ISSN 0010-0765
R&D Projects: GA AV ČR IAA4040007
Institutional research plan: CEZ:AV0Z4040901
Keywords : FeH-ZSM-5 * N2O oxidation of benzene * Fe-zeolites
Subject RIV: CF - Physical ; Theoretical Chemistry
Impact factor: 1.041, year: 2003

NH4-(Fe)ZSM-5 zeolites with concentrations of Fe ranging from 30 to 2000 ppm, introduced into zeolites during their synthesis, either calcined in a dry oxygen at 720 K or steamed at 870 K in an oxygen stream with 30 % water vapor, were investigated in benzene oxidation with N2O to phenol and SCR-NOx to nitrogen. The concentration of Broensted and Lewis sites was determined by quantitative analysis of IR spectra of adsorbed d3-acetonitrile. The changes in Fe ion coordination were monitored by ESR spectra of Fe(III) ions. The Fe ions have been shown to control their performances in the above reactions, while the Al-related acid sites play only minor role. The steamed zeolites compared to calcined ones exhibited substantially higher activity in oxidation of benzene with N2O to phenol, while the SCR-NOx reaction to nitrogen was considerably suppressed. The steaming resulted in a dramatic decrease in concentration of Broensted sites, low concentration of Lewis sites.
Permanent Link: http://hdl.handle.net/11104/0078267