Modified seeding method to produce hierarchical nanocrystalline ZSM-5 zeolite

A series of ZSM-5 nano-zeolites with hierarchical porosity was prepared by a modified seed-induced method using a mixture of silicate-1 and commercial Na-ZSM-5 zeolite as a seed to reduce the production cost. The XRD and FTIR results proved that the pure ZSM-5 phase with a high degree of crystallinity was crystallized. Furthermore, the synthesized samples using a mixture of silicate-1 and commercial ZSM-5 as a seed exhibited more dealumination during the hydrothermal aging process, resulting in a higher S-meso/S-BET ratio than other samples and the highest ratio of Bronsted/Lewis acid sites among all the samples. The SEM and BET results also confirmed that the final pH after the synthetic process extensively affected the morphology, specific area and pore volume of products. The purposed method by employing a lower amount of the organic template and silica source might lead to a more economical and environmentally friendly approach for the hierarchical ZSM-5 zeolite production to benefit the relevant industries.