PETR 6 |
| Hierarchical mesoporous M-ZSM-5 was prepared using an amphiphilic organosilane as a templating agent. XRD and sorption data indicated that M-ZSM-5 is a mesoporous material with ZSM-5 framework. 29Si MAS NMR spectroscopy revealed that M-ZSM-5 was highly crystalline, like conventional ZSM-5. 27Al MAS NMR spectroscopy showed that most of the aluminum atoms were in tetrahedral coordination and 2-methyl-2-pentene isomerization exhibited that M-ZSM-5 possessed strong acidity, similar to ZSM-5. The Friedel-Crafts benzylation of benzene by benzyl alcohol was used to evaluate the catalytic reactivity of the hierarchical zeolite catalyst. M-ZSM-5 had a much higher catalytic activity than conventional ZSM-5 and amorphous silica-alumina. The apparent rate constant for M-ZSM-5 is 23 times larger than that for ZSM-5. The catalyst could be reused and maintained the initial activity after three cycles. These results indicate that hierarchical zeolites have potential application in Friedel-Crafts alkylations of large molecules. |
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Zeolite Catalysis for Green Chemistry in Synthesis of Chemicals and Fuels
8:20 AM-12:00 PM, Sunday, April 6, 2008 Morial Convention Center -- Rm. 209, Oral
Division of Petroleum Chemistry |