Synthesis and characterization of zeolite (MFI) membrane on anodic alumina

Zeolite crystals, up to 130 µm, have been grown on anodic alumina supports. ZSM-5 crystals were hydrothermally synthesized in a high H2O : SiO2 ratio solution without adding aluminium. The anodic alumina was used not only as a support but also as a source of aluminium in the preparation of ZSM-5 crystals. Horizontal and vertical growths of zeolite crystals were observed on the anodic alumina substrate. The strength of adhesion between zeolite and anodic alumina was excellent, because the zeolite was anchored inside the porous anodic alumina. This is the first time that continuous polycrystalline films of ZSM-5 crystals have been prepared on anodic alumina.