In the present work, the effect of different mixtures of structure-directing agents (SDAs) on the structure and morphology of silicoaluminophosphate (SAPO-34) molecular sieves has been investigated. For this reason, triethylamine (TEA), diethylamine (DEA), n-butylamine (BA), and various combinations of them were used as organic templates for the synthesis of SAPO-34. The prepared samples were well characterized by X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FT-IR), field emission scanning electron microscopy (FESEM), transmission electron microscopy (TEM), and N2 adsorption-desorption techniques. To explain the effect of the template on the SAPO-34 structure, Monte Carlo simulations were performed. In the simulation section, to survey the effect of the template nature on the formation of SAPO-34, the relation between the host framework and guest template was considered. The experimental studies revealed that the TEA template has an effective role in the mesoporosity and surface area of the prepared samples. The theoretical calculations showed that the prepared samples with the participation in the TEA template present more non-bonding interactions with the SAPO-34 molecular sieves.

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