| Autor: |
B. Staudte, Eike Brunner, K. Beck, M. Koch, D. Zscherpel, Harry Pfeifer |
| Rok vydání: |
1994 |
| Předmět: |
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| Popis: |
Summary The present low-temperature 1 H MAS NMR investigations yield new information concerning the nature of acid sites responsible for the enhanced catalytic activity of “mildly” hydrothermally treated H-ZSM-5 zeolites. The enhancement of catalytic activity is either caused by Br0nsted acid sites of enhanced strength of acidity with a relatively broad distribution of deprotonation energies or by a synergism between Brensted acid sites of “normal” strength of acidity and Lewis acid sites. Furthermore, the existence of a new signal due to bridging hydroxyl groups influenced by an additional interaction with the zeolitic framework could be shown in H-ZSM-5 zeolites. |
| Databáze: |
OpenAIRE |
| Externí odkaz: |
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