Microwave-assisted hydrothermal synthesis of zeolite films on ceramic supports

Zeolite films were formed on ceramic supports by a novel microwave-assisted hydrothermal method and were characterized by XRD, SEM, FTIR and BET surface area. The two-stage synthesis technique consists of microwave heating of supports saturated with precursor solution to form a thin layer of zeolite nano-seeds, followed by hydrothermal treatment to crystallize MFI zeolite. The resulting zeolite formation time was drastically reduced and the BET surface area of the product was double that obtained using conventional hydrothermal method. The dipping time, microwave heating time, power and hydrothermal heating time influence the amount of zeolite formation, the BET surface area and preferred orientation of the zeolite film. This new method of seed-film growth using a simple domestic microwave oven has the advantages of a two-stage synthesis technique, allowing independent control of nucleation and crystallization to obtain an optimum zeolite film and reduce the synthesis time.