Synthesis and Characterization of Mesoporous Mordenite Zeolite Using Soft Templates

摘要

Mesoporous mordenite zeolite samples were prepared by steam assisted conversion (SAC) method using soft templates (Brij 58, Pluronic P123, Pluronic F127 and CTABr) as drivers for mesopore generation. Samples were characterized by physical adsorption and desorption of N-2, X-ray diffraction (XRD), temperature programmed desorption of ammonia (TPD/NH3) and infrared spectral analyses (FT-IR). Results indicated that samples using CTABr surfactants template showed significant mesoporosity, which was evidenced by an increase in the mesopore volume determined by the Barrett-Joyner-Halenda (BJH) method. XRD analysis and TPD/NH3 confirmed that almost all samples had mordenite structure and that total acidity was maintained. However, when a large amount of CTABr was used, a crystallinity loss was observed. Furthermore, samples were evaluated in a catalytic cracking reaction of n-heptane at 653 K and mesoporous mordenite sample showed higher catalytic activity and low deactivation rate as compared with a standard mordenite sample.