Dry-gel synthesis of shaped binderless zeolites composed of nanosized ZSM-5

Shaped binderless ZSM-5 zeolites are prepared via a dry-gel conversion (DGC) technique from aluminosilicate extrudates, where the addition of seed gels not only provides crystal nuclei for rapid crystallization of zeolite but also controls the size of ZSM-5 crystal. Furthermore, the introduction of amine into the steam favors the formation of nanosized ZSM-5 zeolite. Especially, the morphology of these aluminosilicate extrudates well kept in the crystallization process. The obtained shaped zeolites are characterized by X-ray diffraction (XRD), nitrogen adsorption analysis, and scanning electron micrographs (SEM). The shaped zeolites show hierarchical structure with high mesopore volume (0.22 cm3 g−1) and demonstrate similar activity as commercial ZSM-5 samples in the transformation of i-propanol to hydrocarbons reaction.

Graphical abstractFigure optionsDownload full-size imageDownload as PowerPoint slideHighlights► Columned shaped ZSM-5 zeolites were synthesized by a dry-gel conversion method. ► The seed gel and the amine controlled the assembly of nano-sized zeolite ZSM-5. ► Shaped ZSM-5 zeolites possessed hierarchical structure. ► Shaped ZSM-5 zeolites showed excellent mechanical strength.