A mesoporous beta zeolite was hydrothermally prepared directly by silanizing silica without any mesoporous template via the bond-blocking principle.

A hierarchical zeolite Beta has been prepared by a feasible one-pot and one-step method, which is suitable for application in industrial production. The synthesis is a simple hydrothermal process with low-cost raw materials, without adding alcohol or adding seeds, and without aging, recrystallization, and other complex steps. The hierarchical zeolite Beta is a uniform nanocrystal (20–50 nm) aggregation with high external surface area (300 m2/g) and mesoporous volume (0.50 cm3/g), with the mesoporous structure composed of intercrystal and intracrystal pores. As an acid catalyst in benzylation of naphthalene with benzyl chloride, the hierarchical zeolite Beta has shown high activity in the bulky molecule reaction due to its introduction of mesostructure.

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A series of novel mesoporous MCM-41 (Mobil Composition of Matter No. 41) materials has been synthesised using pre-organo-functionalised fumed silica as the silica source. Subsequent X-ray diffraction, nitrogen/argon adsorption and transmission electron microscopy analyses indicated that the additional mesopores formed in silica walls seem to cross the inherent hexagonally arranged channels, affording interconnected structural mesopores. Compared with the conventional MCM-41 material featuring single cylindrical pores, the newly prepared materials have a larger surface area (1450 m 2 /g), and their adsorption capacity for n-heptane has been enhanced in the low-pressure region, which presumably would be highly beneficial to the abatement of low-concentration volatile organic compounds.

A continuous selective catalysis of 4-(Trifluoromethoxy)aniline, a key intermediate in the preparation of riluzole, was studied using a micropacked-bed reactor (µPBR) packed with Pt/BAC catalysts. The effects of technological parameters such as solvent types, gas flow rates and liquid flow rates were investigated. It was indicated that the continuous hydrogenation process exhibited higher efficiency, selectivity and safety with less energy consumption compared to the traditional batch reduction process. The newly developed reactor system demonstrated a sustained and stable catalytic performance after 20 h running.

Due to the intricacy aromatic dinitro compound hydrogenation processes, it is difficult to attain high conversion and selectivity using merely modified catalysts in batch reactors. The micropacked-bed reactor (μPBR) offers efficient heat and mass transfer, a precise and controllable reaction process, and a high level of safety. In this work, the hydrogenation of 2,4dinitroanisole was selected as the model reaction, and a variety of catalysts were utilized in the continuous flow system based on μPBR for hydrogenation of 2,4-dinitroanisole. During 960 minutes of operation, the synthesis of 2,4-diaminoanisole was carried out using a Pd (OH) 2 /C catalyst and the optimal process condition, yielding 100 % conversion, 99.5 % selectivity, and the favorable durability. For the hydrogenation of relevant aromatic dinitro compounds, the continuous flow system demonstrates exceptional performance.

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