It has long been a dream to construct hierarchical zeolites by a really simple and cost-effective method which is feasible in industry. Here we provide an alternative approach in which the crystallization kinetics is regulated by solely changing the added amount of NaOH in the initial gel of a traditional zeolite and then the adjustment of the morphology and structure of the zeolite products is realized. This approach overcomes most of the limitations associated with the popular methods, such as complex operations and costly secondary templates. As an example, hierarchical ZSM-5 zeolite is prepared with using the most common raw materials and synthesis technology which used in the large-scale production of traditional zeolites. The crystallization process of the hierarchical ZSM-5 zeolite is investigated in detail and compared with the microporous zeolite. The results indicate that the increase of NaOH concentration in the synthesis system can enhance the rate of nucleation but the hierarchical pore structure can be formed only under the moderate concentration. The crystallization of the hierarchical ZSM-5 zeolite takes place by a chain of processes: (i) formation of wormlike precursors, (ii) aggregation of the precursors, (iii) condensation of the precursors and formation of internal voids, (iv) formation of external shell layers. The performance studies show that the obtained hierarchical ZSM-5 zeolite possesses significantly enhanced diffusion property and superior ability for catalytic cracking bulky molecules.

通过一种在工业上可行的非常简单且具有成本效益的方法来构造分级沸石一直是一个梦想。在这里，我们提供了一种替代方法，其中通过仅改变传统沸石的初始凝胶中NaOH的添加量来调节结晶动力学，然后实现沸石产品的形态和结构的调节。这种方法克服了与流行方法相关的大多数限制，例如复杂的操作和昂贵的辅助模板。例如，采用最常用的原材料和合成技术（用于大规模生产传统沸石）制备分级ZSM-5沸石。详细研究了分层ZSM-5沸石的结晶过程，并将其与微孔沸石进行了比较。结果表明，合成体系中NaOH浓度的增加可以提高成核速率，但只有在中等浓度下才能形成分层的孔结构。分级ZSM-5沸石的结晶是通过一系列过程进行的：（i）蠕虫状前体的形成，（ii）前体的聚集，（iii）前体的缩合和内部空隙的形成，（iv）形成外壳层。性能研究表明，所获得的分级ZSM-5沸石具有显着增强的扩散性能和优异的催化裂解大分子的能力。结果表明，合成体系中NaOH浓度的增加可以提高成核速率，但只有在中等浓度下才能形成分层的孔结构。分级ZSM-5沸石的结晶是通过一系列过程进行的：（i）蠕虫状前体的形成，（ii）前体的聚集，（iii）前体的缩合和内部空隙的形成，（iv）形成外壳层。性能研究表明，所获得的分级ZSM-5沸石具有显着增强的扩散性能和优异的催化裂解大分子的能力。结果表明，合成体系中NaOH浓度的增加可以提高成核速率，但只有在中等浓度下才能形成分层的孔结构。分级ZSM-5沸石的结晶是通过一系列过程进行的：（i）蠕虫状前体的形成，（ii）前体的聚集，（iii）前体的缩合和内部空隙的形成，（iv）形成外壳层。性能研究表明，所获得的分级ZSM-5沸石具有显着增强的扩散性能和优异的催化裂解大分子的能力。分级ZSM-5沸石的结晶是通过一系列过程进行的：（i）蠕虫状前体的形成，（ii）前体的聚集，（iii）前体的缩合和内部空隙的形成，（iv）形成外壳层。性能研究表明，所获得的分级ZSM-5沸石具有显着增强的扩散性能和优异的催化裂解大分子的能力。分级ZSM-5沸石的结晶是通过一系列过程进行的：（i）蠕虫状前体的形成，（ii）前体的聚集，（iii）前体的缩合和内部空隙的形成，（iv）形成外壳层。性能研究表明，所获得的分级ZSM-5沸石具有显着增强的扩散性能和优异的催化裂解大分子的能力。