Studies in the Crystallization of Ferrierite (FER) Type Zeolites in Presence of Promoting Medium

The zeolite Ferrierite (FER) was synthesized from the hydrogel containing template and promoting medium. The kinetic features of the ferrierite crystallization with varying SiO2/Al2O3 ratio are reported. The apparent activation energies for nucleation (En) and crystallization (Ec) were evaluated applying the Arrhenius equation. The rates of both nucleation and crystallization have been found to increase significantly in the presence of promoters like ClO4-, PO4-3 and SO4-2 oxyanions during hydrothermal synthesis. The significant enhancement of the FER crystal growth rate due to promoting medium has been attributed to its greater polarizing and rapid condensation ability of tetrasiloxy silane species [Si-(O-Si)4]. The crystalline FER products obtained from promoting medium were characterized by XRD, SEM, TG/DTA, IR, NMR and sorption techniques.