| Autor: |
A.S. Kharitonov, Konstantin A. Dubkov, L.V. Pirutko, Vladimir I. Sobolev, E. A. Paukshtis, Mikhail A. Rodkin, G.I. Panov |
| Rok vydání: |
1996 |
| Předmět: |
|
| Zdroj: |
Applied Catalysis A: General. 141:185-192 |
| ISSN: |
0926-860X |
| DOI: |
10.1016/0926-860x(96)00055-5 |
| Popis: |
Oxidation of benzene to phenol with nitrous oxide being an untypical reaction for zeolite catalysis arouses a great interest among researchers. Several hypotheses concerning reaction mechanism are discussed. Some of them assume a key role of the Bronsted acid centers (BAC), though few experimental support for this idea is available. The goal of this work is to study the Bronsted acidity of FeZSM-5 zeolite catalyst (0.13 wt.% Fe 2 O 3 ) to reveal a relationship (if any) between the BAC concentration and the catalytic activity in benzene oxidation. Various pretreatments of the sample including a high-temperature calcination up to 900°C were used to vary the BAC concentration, which was measured by infrared spectrometry. No evidence of the Bronsted acidity importance for catalyzing the reaction was found. What is more, a formal inverse correlation was discovered. Thus, a manifold decrease in BAC concentration was accompanied by a remarkable increase in the oxidation rate, with a small acid recreation under the reaction conditions used. The obtained results support an earlier suggested redox mechanism of the reaction involving a special oxygen form produced at N 2 O decomposition on Fe-containing active sites. |
| Databáze: |
OpenAIRE |
| Externí odkaz: |
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