We reported a perfect strategy for the fabrication of Cu-encapsulated hierarchical MEL zeolites by a simple post-desilication−recrystallization strategy. The Cuencapsulated hierarchical MEL zeolites exhibited extraordinary selectivity in the liquid alkylation reaction of mesitylene and benzyl alcohol compared with hierarchical MEL zeolites, indicating that the additional Cu species located in the matrix of MEL zeolites can effectively inhibit self-etherification of benzyl alcohol. In addition, the selectivity of 2-benzyl-1,3,5trimethylbenzene for the Cu-containing hierarchical MEL zeolites was in the order of

A series of iron-encapsulated hierarchical ZSM-5 zeolites with nanosheet-assembled structure were designed and successfully fabricated, and their catalytic performance was investigated for the selective catalytic reduction of NO x with NH 3 (NH 3 -SCR). Because of the synergy between the welldispersed Fe active species and the Brønsted acidic framework of zeolites, the Fe-containing ZSM-5 catalyst displayed excellent catalytic performance, and density functional theory (DFT) calculation data indicated that capturing NH 3 was the main factor that mediates the NH 3 -SCR process. In addition, the resultant zeolite catalysts exhibited a good resistance to SO 2 and H 2 O, which was very competitive for practical application to reduce NO x emissions. Furthermore, in situ DRIFT measurements revealed that the generation of inactive nitrate species led to the decrease of zeolite activity in a high-temperature region.

Zeolite belongs to one of the most important families of solid acid catalysts in chemical industries. It is, however, severely constrained by the diffusion limitation for bulky molecules, a lack of multifunctionality for sequential reactions and pore adaptability toward specific adsorbates due to its small micropore size and simple aluminosilicate framework. Introducing mesopores into a zeolite toward realizing hierarchical zeolites is a prevailing strategy but one that usually suffers from compromised crystallinity as well as insufficient interconnectivity and openness of the mesopores. Herein, a novel acid-redox co-functionalized single-crystalline zeolite with highly open and interconnected mesopores is designed and fabricated. As a proof-of-concept study, we integrate solid acid and Fe-oxy redox sites into a hierarchical MEL zeolite with wellcharacterized microporosity and mesoporosity. This zeolite exhibits superior activity and stability toward alkylation between mesitylene with benzyl alcohol, arising from greatly facilitated intra-crystal molecular diffusion, mitigated metal leaching and optimized adsorbate-pore wall interactions.

The hierarchical structure of zeolites plays a crucial role in determining their catalytic performance. Here, the effect of the hierarchical architecture and surface topology of pillared MWW zeolites on the catalytic properties of liquid alkylation between mesitylene and benzyl alcohol was investigated. Pillared MWW zeolite catalysts exhibited excellent activity (∼100% conversion) due to their elegant pore architecture, which could largely improve the accessibility of bulk molecules toward active sites on the external surface. In addition, molecular simulation showed that lamellar MWW zeolites with a 12-membered ring semicup surface topology could more effectively accommodate and stabilize the large intermediates formed in alkylation reactions compared with MFI zeolites, resulting in outstanding selectivity for 2-benzyl-1,3,5-trimethylbenzene (∼100%). The Thiele modulus (φ) and effectiveness factor (η) verified that the resultant pillared MWW zeolites possessed a high degree of utilization without internal diffusion constraints under the present reaction conditions.

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