Hierarchical ZSM-5 zeolite with radial mesopores is controllably synthesized using piperidine in a NaOH solution. The piperidine molecules enter the zeolite micropores and protect the zeolite framework from extensive desilication. The areas containing fewer aluminum atoms contain fewer piperidine protectant molecules and so they dissolve first. Small amounts of mesopores are then gradually generated in areas with more aluminum atoms and more piperidine protectant. In this manner, radial mesopores are formed in the ZSM-5 zeolite with a maximal preservation of the micropores and active sites. The optimal hierarchical ZSM-5 zeolite, prepared with a molar ratio of piperidine to zeolite of 0.03, had a mesopore surface area of 136 m²·g⁻¹ and a solid yield of 80%. The incorporation of the radial mesopores results in micropores that are interconnected which shortened the average diffusion path length. Compared to the parent zeolite, the hierarchical ZSM-5 zeolite possesses more accessible acid sites and has a higher catalytic activity and a longer lifetime for the alkylation of benzene.

使用哌啶在NaOH溶液中可控地合成具有径向中孔的ZSM-5分子筛。哌啶分子进入沸石微孔并保护沸石骨架免受广泛的脱硅作用。包含较少铝原子的区域包含较少的哌啶保护剂分子，因此它们首先溶解。然后在具有更多铝原子和更多哌啶保护剂的区域中逐渐生成少量中孔。以这种方式，在ZSM-5沸石中形成了径向中孔，其中最大程度地保留了微孔和活性位。以哌啶/沸石的摩尔比为0.03制备的最佳分层ZSM-5沸石的中孔表面积为136 m ² ·g ^-1固体产率为80％。径向中孔的结合导致相互连接的微孔，这缩短了平均扩散路径的长度。与母体沸石相比，分层ZSM-5沸石具有更易接近的酸性位点，并具有更高的催化活性和更长的苯烷基化寿命。