The large mesoporous surfaces of hierarchical zeolites without confinement of the active sites leads to the question of whether the shape selectivity of these zeolites is essentially altered. The hydroisomerization of n-hexane to mono- and dibranched C₆ isomers was carried out as a model reaction governed by the shape selectivity to obtain insight into the effects of the secondary mesoporous structure. A series of micro- and micromesoporous ZSM-5, MOR, ^∗BEA, and Y zeolites with regular microporosity or well-developed mesoporosity were prepared by synthesis and postsynthesis treatment, and their selectivity was investigated. We demonstrate that isomerization is exclusively controlled by concurrent interaction of the reactant with the Brønsted site and the inner walls of the zeolite channels, irrespective of the mesoporosity. The reaction is facilitated only by a combination of dispersive forces in the inert void and acid sites in the confined environment. The shape selectivity of micromesoporous zeolites is thus fully preserved.

没有限制活性位的分级沸石的大的介孔表面导致这些沸石的形状选择性是否实质上改变的问题。的加氢异构化Ñ正己烷单-和dibranchedÇ ₆异构体进行如通过形状选择性约束以获得洞察次级介孔结构的作用的模型反应。一系列微孔和微孔的ZSM-5，MOR，^*通过合成和后合成处理制备了具有规则微孔性或发达的中孔性的BEA和Y沸石，并研究了它们的选择性。我们证明，异构化仅受反应物与布朗斯台德位点和沸石通道内壁的并发相互作用控制，而与介孔率无关。仅在惰性空间中的分散力和密闭环境中的酸性部位共同促进反应。因此完全保留了微孔沸石的形状选择性。