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Sheet‐like ZSM‐5 has been regarded as a promising material for catalytic applications due to its diffusion superiority. However, it still remains a challenge to obtain a desirable sheet‐like morphology because of the complex synthesis process of zeolites. Here, a facile strategy for synthesizing sheet‐like ZSM‐5 is developed by only adding ethanol as zeolite growth modifier in the synthesis gel. It is thought that ethanol might be preferentially absorbed on the {010} surface of zeolite crystals, interact with the exposed silicon hydroxyl groups on the crystal {010} facet, and suppress the growth of b axis, resulting in the sheet‐like shape. Through finely tunning synthesis parameters, sheet‐like ZSM‐5 crystals with thin b‐axis thickness of 90 nm and different aspect ratios could be obtained. Owing to its shorter diffusion path and optimized acidity, sheet‐like ZSM‐5 exhibits better catalytic performance than conventional ZSM‐5 in the alkylation of benzene with ethanol. [ABSTRACT FROM AUTHOR]

The synergistic effect between metal and acid sites has been considered to be of great importance to n-alkane hydroisomerization catalyzed by bifunctional catalysts. Herein, we report a facile mercaptosilane-assisted in situ synthesis approach to achieve stable and highly dispersed small Pt nanoparticles supported on HL zeolite catalysts (Pt/HL-SH) for n-hexane hydroisomerization. In comparison with the catalysts (Pt/HL-C) synthesized by a traditional ion-exchange method, the Pt/HL-SH catalysts show both high activity and excellent catalytic stability and also no obvious sintering of Pt nanoparticles is observed during the reaction due to the fact that the Pt/HL-SH catalysts possess both higher dispersion of Pt particles within the HL nanocrystals and more mesopores produced by mercaptosilane. Moreover, the regeneration stability of n-hexane hydroisomerization over Pt/HL-SH catalysts was also examined by five continuous cycles, demonstrating excellent regeneration properties. Thus, the mercaptosilane-assisted in situ synthesis approach is a promising way to prepare bifunctional catalysts for enhancing their catalytic performance in n-alkane hydroisomerization. [ABSTRACT FROM AUTHOR]

Incorporating mesopores into ZSM-5 zeolite to form a hierarchical structure has been regarded as an important approach to enhance the diffusivity and catalyst lifetime for light alkane aromatization. Herein, hierarchical ZSM-5 nano-aggregated microspheres were simply and directly synthesized and characterized using TPAOH as a single template without any mesoporous templates or zeolite seeds. The size of the ZSM-5 microspheres and the distribution of mesopores could be regulated by controlling the alkalinity of the synthesis gel. A possible self-assembly mechanism was proposed based on tracing the formation process of ZSM-5 microspheres with crystallization time. The ZSM-5 microspheres modified with Zn were applied in n-hexane aromatization and exhibited better catalytic stability than conventional mono-dispensed microporous ZSM-5 due to the existence of accessible mesopores. [ABSTRACT FROM AUTHOR]

[Display omitted] • LTL-zeolite was used as a novel support for selective phenol hydrogenation. • LTL has one-dimensional large-pore diffusion system and adjustable base-acid sites. • Palladium nanoparticles were in-situ encapsulated within LTL-zeolite. • High Pd dispersions were obtained after encapsulation. • Switching chemical microenvironments around Pd sites changed the kinetic profiles. Cyclohexanone, as a significant raw material in the production of nylon 6 and nylon 66, is preferentially synthesized via selective phenol hydrogenation while the key point is to modulate the acidic/basic properties and metal dispersion of the catalytic system. Here, we report the fabrication of Pd@L core–shell catalysts via the in-situ encapsulation of Pd nanoparticles within the L zeolite with a one-dimensional large-pore diffusion system for the selective hydrogenation of phenol to cyclohexanone. The different Pd amounts and acidic/basic properties of the L zeolite catalyst were modulated to study the effects of the microenvironment around the Pd centers in the Pd@L on the catalytic performances of selective phenol hydrogenation. The results show that the basicity of L zeolite greatly favors high selectivity to cyclohexanone. In contrast, modulating the microenvironment to weak or strong acid states can result in the dehydration product forming on the acid sites or even the suppression of phenol hydrogenation. The conversion of phenol increases from 14.0% to 99.9% and meanwhile the selectivity of cyclohexanone ranges from 67.5% to 93.8%. In the optimum condition, the obtained Pd@KL catalyst can demonstrate excellent catalytic performance with the phenol conversion of 99.9% and the cyclohexanone selectivity of around 93.8%. Our work presents a promising tactic to effectively control the target reaction pathway by means of maneuvering the microenvironment in the proximity of metal nanoparticles. [ABSTRACT FROM AUTHOR]