Mesoporous MFI zeolite material from silica–alumina/epoxy-resin composite material and its catalytic activity

Although the versatilities of zeolitic materials are widely known to chemists and materials scientists, their exclusive microporosity sometimes causes various defections especially in the diffusion of reactant and product molecules in catalytic reactions. Silica–alumina/epoxy-resin composite materials were obtained from TMOS (tetramethoxysilane), aluminum acetylacetonate and bisphenol A diglycidyl ether with a cyclic acid anhydride as both condensation and curing reagents. Hydrothermal treatment of the composite materials with TPAOH (tetra-n-propylammonium hydroxide) crystallized the amorphous silica–alumina part to the MFI zeolite crystalline phase and induced the phase separation of epoxy-resin domain from the zeolite phase at the same time, forming both zeolite microporosity and mesoporosity in the solid catalyst after calcination. The mesoporous MFI zeolite thus prepared had a good catalytic activity in liquid phase Friedel–Crafts benzylation reaction. The mesoporous channels fabricated in the MFI zeolite material enhanced the diffusion of reactants and products in the solid matrix, and thus it showed a better catalytic activity in the benzylation of toluene together with the high selectivity of the mono-substituted para-isomer. The new methodology reported in this paper to produce the mesoporous zeolite materials will promote the chemistry and the applications of zeolite catalysts and related materials.

Mesoporous MFI zeolite material with high catalytic activity for Friedel-Crafts reaction was successfully prepared by hydrothermal treatment of silica-alumina/epoxy-resin composite material with TPAOH.Figure optionsDownload as PowerPoint slideResearch highlights
► Silica–alumina/epoxy-resin composite materials were prepared by using cyclic acid anhydride.
► Mesoporous MFI zeolite was obtained by the calcination of hydrothermally treated composite.
► Mesopores are formed by the phase separation process during the hydrothermal treatment.
► Mesoporous MFI zeolite obtained had a high activity and selectivity in Friedel–Crafts reaction.