One-pot synthesis of core-shell structured SSZ-13 zeolite using aluminum isopropoxide as an aluminum source

Abstract

SSZ-13 zeolite with core-shell structure was successfully synthesized by a facile one-step hydrothermal synthesis method using aluminum isopropoxide as an aluminum source. The obtained samples were characterized by XRD, SEM and N2 adsorption/desorption techniques. According to the results, the synthesized SSZ-13 zeolite showed unequivocally the core–shell structure with sub-micron crystalline aggregated SSZ-13 shell formed by epitaxial growth. Moreover, the core-shell structured SSZ-13 possessed distinct pore structure compared with conventional SSZ-13 synthesized by using aluminum nitrate as aluminum source. SEM images demonstrated the formation process of the core-shell structure. Crystals with an spherical morphology were formed from the dissolved Si and Al species, and then amorphous gel precursors deposited on the surface of large SSZ-13 cores and converted into sub-micron SSZ-13 crystals.