Hierarchical SSZ-13 microspheres, with abundant mesoporous channels, have been successfully synthesized by addition of calcined SSZ-13 crystals in the starting gel in the absence of any organic templates. This strategy not only remarkably reduces the production cost and environmental pollution, but also significantly decreases the crystallization time as well as evidently reducing the zeolite crystal sizes in many cases. The synthesized sample was characterized by XRD, BET, ICP, SEM, TEM, TG, and NH -TPD, which indicates that the organic template free synthesized SSZ-13 exhibits high crystallinity, textural properties, and acidity. Moreover, the synthesized hierarchical SSZ-13 catalyst shows outstanding performance in the methanol-to-olefin (MTO) reaction, with slightly higher ethylene plus propylene selectivity and prolonged catalyst lifetime as compared to the templated SSZ-13 catalyst.

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Hierarchical SSZ-13 were quickly synthesized by adding a small quantity of hydrofluoric acid in the starting gel using aluminum isopropoxide as aluminum source.

Ag modified mesoporous molecular sieves Ti-HMS were prepared by in-situ synthesis (Ag/Ti-HMS-I), deposition-precipitation method (Ag/Ti-HMS-D) and ultrasound-assisted impregnation methods (Ag/Ti-HMS-U), respectively. The catalytic performance of catalysts in the oxidative desulfurization(ODS) of benzothiophene with hydrogen peroxide (H2O2) has been investigated. The physicochemical properties of the catalysts were characterized by XRD, SEM, BET and FT-IR techniques. Experimental results showed that the catalyst Ag/Ti-HMS-U exhibited the best catalytic activity, and this maybe because the catalyst possessed relatively good mesoporous structure and high Ag dispersion. Under the best operating condition for the catalytic oxidative desulfurization: temperature 60 °C, atmospheric pressure, 0.1 g catalysts, 8 molar ratio of hydrogen peroxide to sulfur, using acetonitrile as extraction solvent for double extraction, the sulfur content in model diesel fuel (MDF) was reduced from 800 ppm to 17 ppm with 97.8% of total sulfur after 1 h.