Solid state crystallization process and mechanism of B Al ZSM 5 zeolite from a dry gel of B 2O 3·Al 2O 3·SiO 2 in the mixture of ethylamine and water vapour were studied by 11 B, 27 Al, 29 Si, 13 C MAS NMR, XRD and IR. The extranetwork trigonal BO 3 units in the gel play an important role in the process of crystallization. The change of chemical environment around Al atoms is complicated in the process of crystallization. Octahedral Al O groups existing in the intermediate products do not appear in both the initial gel and final product. Silicon is mainly present as hydroxyl compounds, and the extrastructural Si O groups detected in the process of crystallization disappear after complete crystallization. Ethylamine plays the role of both template and reactant. It acts with the boron , aluminum , and silicon hydroxyls through hydrogen bonding and promotes the crystallization process. The relative crystallinity of the final B Al ZSM 5 product is about 93% as measured with 11 B MAS NMR and IR.
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