Engineering of zeolite BEA crystal size and morphology via seed-directed steam assisted conversion.

ABSTRACT: The mechanism of seeding of zeolite BEA via steam assisted conversion has been studied using BEA seeds with different composition. The catalysts are characterized by X-ray diffraction, scanning and transmission electron microscopy, nitrogen adsorption-desorption, Hg-porosimetry, X-ray fluorescence and TPD of ammonia, and evaluated in benzene alkylation with propene. The results show that variation of the SiO₂/Al₂O₃ ratio from 25 to 250 in BEA seeds changes the mechanism of seeding from "core-shell" to a "dissolution" mechanism, which can serve as a tool for engineering the morphological, textural and catalytic properties of BEA zeolites. Al-rich seeds (SiO₂/Al₂O₃ = 25) do not dissolve during gel preparation and initia

SUBMITTER: Bok TO 

PROVIDER: S-EPMC9057372 | biostudies-literature | 2020 Oct

REPOSITORIES: biostudies-literature