Hierarchical ZSM-5 Zeolite Synthesized Only with Simple Organic Templates

Abstract

Hierarchical zeolites have attracted more and more attention due to their excellent diffusion and mass transfer performance. However, synthesis of most hierarchical zeolites requires long-chain organic templates, which could increase preparation cost. Here, hierarchical ZSM-5 zeolites were successfully prepared with simple organic templates (triethylenetetramine) in a rotating oven. Besides hierarchical structure, the crystal size of ZSM-5 also decreased when they were synthesized under dynamic hydrothermal conditions. The samples were analyzed using various physicochemical characterizations, such as X-ray diffraction (XRD), X-ray fluorescence (XRF), scanning electron microscopy (SEM), Fourier transform infrared spectra (FT-IR), temperature-programmed desorption of ammonia (NH3-TPD) and N2 adsorption–desorption. The hierarchical ZSM-5 zeolites synthesized in a rotating oven presented better catalytic activity and stability in iso-butane cracking reaction than those synthesized under conventional static hydrothermal conditions.