In this work, HZSM-5 zeolite was synthesized using n-butylamine as a template under hydrothermal conditions. The prepared samples were carefully characterized by X-ray diffraction (XRD), transmission electron microscopy (TEM), scanning electron microscopy (SEM), pyridine-adsorbed Fourier transform infrared spectra (Py-FTIR) and ammonia temperature-programmed desorption (NH3-TPD) techniques. The morphology of the prepared zeolites was changed with the initial gel composition. The influence of OH–/Template and H2O/Template ratios on the morphology, mesoporosity, acid properties and crystal size of the synthesized zeolites were evaluated. Also, the structural effects of the prepared zeolites on the catalytic performances of the methanol to propylene (MTP) process were examined. The results indicated that with increasing the external surface area and mesopore volume of the catalysts, the propylene selectivity was improved in the order of A4˃A3˃A2˃A1. Also, there was a direct relationship between the deactivation of catalysts and their acidic properties. These results are derived from laboratory data and need to be re-examined on a larger scale to ensure their accuracy on an industrial scale.

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