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High-performance hierarchical cheese-like C-ZSM-5 nanocrystals are successfully prepared by acid–base treatment and are evaluated for oxidative desulfurization of dibenzothiophene. The acid–base treatment can generate a large number of Si-OH bonds and an open-mesoporous structure, which is conducive for the dispersion of TiO2 and also for the transport of dibenzothiophene and its oxidation products simultaneously. The catalytic results indicate that the hierarchical cheese-like C-ZSM-5 nanocrystals are highly active catalysts for the oxidative desulfurization of dibenzothiophene due to open mesoporosity. Complete conversion was obtained within 80 min at 338 K. The excellent performance is due to the large number of active framework sites and open mesopores generated by post-processing. [ABSTRACT FROM AUTHOR]

The comparatively small micropore dimensions of bulk ZSM-5 zeolites often limit both the adsorption and catalytic conversion of large organic molecules. Here, we report that ZSM-5 zeolites were prepared by a gel-casting technique with microporous, mesoporous and macroporous hierarchical structures. The as-prepared samples were characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM), nitrogen adsorption, temperature-programmed-desorption of ammonia (TPD-NH3) and Fourier transform infrared spectroscopy (FTIR) measurements. The hierarchical structured ZSM-5 zeolites were used to carry out catalytic cracking of 1,3,5-triisopropyl benzene and n-hexadecane. The results show that, compared with traditional ZSM-5, Beta or Al-MCM-41, this modified ZSM-5 displayed preferable catalytic activity and selectivity. [ABSTRACT FROM AUTHOR]

[Display omitted] • Hierarchical ANA zeolites with unique nanosheets-assembled spheres morphology were synthesized. • The addition of seeds and proper aging time are necessary condition for the synthesis. • The formation mechanism was studied experimentally. • The hierarchical ANA showed high adsorption capacity of Pb2+. A hierarchical ANA zeolite with nanosheets-assembled spheres (SAS-ANA) was successfully prepared and used for the removal of lead ions from the aqueous solution. The characterization of the sample was investigated by X-ray Diffraction (XRD), Scanning electron microscopy (SEM), Transmission electron microscopy (TEM) and Surface area (BET). A possible mechanism was proposed and verified by experiments. In the Pb2+ ions adsorption experiment, SAS-ANA adsorbed almost all the 25 mg of Pb2+ ions dispersed in 100 ml of water within 10 min which was more efficient than that of natural analcime (78.8% in 50 min). And the saturated adsorption capacity of SAS-ANA was 169.3 mg/g, which was much larger than that of natural analcime (67.5 mg/g), ZSM-5 (50 mg/g) and Al-MCM-41 (2 mg/g). [ABSTRACT FROM AUTHOR]