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Hierarchical ZSM‐5 zeolites were synthesized by in‐situ crystallization of mesoporous carbon‐silica composites with a well‐ordered SBA‐15 structure. The hierarchical ZSM‐5 zeolite possessed a rather high external surface area (205 m2/g) and pore volume (0.35 cm3/g) compared with the reference ZSM‐5 zeolite, as well as higher acid‐site accessibility to large molecules. In the naphthalene benzylation reaction, the hierarchical HZSM‐5 zeolite converted approximate 50 % of benzyl chloride in 100 minutes under mild conditions and showed a high stability, which could be ascribed to the improved diffusion ability and acid‐site accessibility. [ABSTRACT FROM AUTHOR]

Ordered mesoporous Zr-Al composite oxide materials (denoted as OMZA-x) with different Zr contents have been synthesized by a solvent evaporation-inducing self-assembly procedure associated with a thermal treatment at 100 °C. A cooperative co-assembly process of amphiphilic triblock copolymer F127 molecules and inorganic hydroxyl species originated from the hydrolysis of Zr and Al precursors was proposed to explain the synthesis of OMZA-x. Compared to ordered mesoporous alumina prepared without introducing Zr species, the resultant OMZA-x exhibited a much more ordered mesostructure combined with a distinct increase in the pore volume and specific surface area. The highly homogenous doping of Zr into the mesopore walls together with the formation of Zr-O-Al bonds can effectively enhance the thermal and hydrothermal stability of OMZA-x. For instance, the ordered mesostructure and excellent textural properties of OMZA-6 prepared with the optimum atomic ratio of Al to Zr of 6 could be well maintained even after a high-temperature treatment at 1000 °C for 1 h or a hydrothermal treatment at 100 °C for 6 h. [ABSTRACT FROM AUTHOR]

• Well-crystallized zeolite Y assembled by nanocrystals with intercrystal mesopores. • The nanocrystal zeolite Y lying on both gel formation and aging at low temperature. • Presence of CTAB improving the assemblies of zeolite Y nanocrystals. • Highly active accessibility and rapid diffusion in the zeolite Y to bulk molecules. Zeolite Y nanocrystal assembly was synthesized by using cetyltrimethyl ammonium bromide (CTAB) under low gelling and aging temperature in the hydrothermal system. XRD, SEM, N 2 adsorption/desorption isotherms, 29Si and 27Al MAS NMR spectra as well as NH 3 -TPD demonstrated that the synthesized zeolite Y is a mesoporous zeolite composed of well-developed nanocrystals with high external surface area, intercrystal mesoporosity and acidity. The conversions of 1,3,5-trimethylbenzene (TMB) and 1,3,5-triisopropylbenzene (TIPB) reflect its superior features for isomerization, selectivity of bulky molecule and catalytic stability. [ABSTRACT FROM AUTHOR]