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Efficient low‐temperature hydrodeoxygenation (HDO) of lignin derivatives to produce biofuels and high value‐added chemicals is still of challenge. Here, we have constructed a high active and stable 0.2 wt.% Pd/MS‐HZSM‐5(30) catalyst, and 94.7 % yield of 2‐methoxy‐4‐methylphenol (MMP) can be achieved in HDO of vanillin (VAN, a typical platform molecule of lignin derivatives) under milder reaction conditions (60 °C, 5 h, molar ratio of VAN/Pd=1200, water phase), outperforming the most works reported recently. Detailed experimental and mechanistic studies demonstrated that the superior catalytic performance was due to the rapid hydrogenolysis of generated intermediate (vanillyl alcohol, VAL) to MMP proceeded in an interfacial microenvironmental created by Pd NPs and acidic sites in Pd/MS‐HZSM‐5(30). These new insights will provide potential guidance for the efficient low‐temperature production of biofuels and valuable chemicals from lignin derivatives or raw lignin. [ABSTRACT FROM AUTHOR]

Direct synthesis of hierarchical zeolites currently relies on the use of surfactant-based templates to produce mesoporosity by the random stacking of 2D zeolite sheets or the agglomeration of tiny zeolite grains. The benefits of using nonsurfactant polymers as dual-function templates in the fabrication of hierarchical zeolites are demonstrated. First, the minimal intermolecular interactions of nonsurfactant polymers impose little interference on the crystallization of zeolites, favoring the formation of 3D continuous zeolite frameworks with a long-range order. Second, the mutual interpenetration of the polymer and the zeolite networks renders disordered but highly interconnected mesopores in zeolite crystals. These two factors allow for the synthesis of single-crystalline, mesoporous zeolites of varied compositions and framework types. A representative example, hierarchial aluminosilicate (meso-ZSM-5), has been carefully characterized. It has a unique branched fibrous structure, and far outperforms bulk aluminosilicate (ZSM-5) as a catalyst in two model reactions: conversion of methanol to aromatics and catalytic cracking of canola oil. Third, extra functional groups in the polymer template can be utilized to incorporate desired functionalities into hierarchical zeolites. Last and most importantly, polymer-based templates permit heterogeneous nucleation and growth of mesoporous zeolites on existing surfaces, forming a continuous zeolitic layer. In a proof-of-concept experiment, unprecedented core-shell-structured hierarchical zeolites are synthesized by coating mesoporous zeolites on the surfaces of bulk zeolites. [ABSTRACT FROM AUTHOR]

A new synthetic strategy is developed for fabricating hierarchically structured zeolite materials, which features the use of cationic non‐surfactant polymers as dual‐functional templates. Y. Han and co‐workers show, on page 1881, that the mutual interpenetration of the polymer and the zeolite networks renders disordered but highly interconnected mesopores in zeolite crystals. This strategy also enables the synthesis of unprecedented core‐shell‐structured hierarchical zeolites. [ABSTRACT FROM AUTHOR]

Constructing hierarchical Zr-BEA zeolites via an alkali etching-free route is still of challenge. Here, we have prepared a hierarchical HR-Zr-BEA from a mesoporous Al-BEA which can be facilely synthesized using commercial chemicals as the structure-directing agent. The structure of HR-Zr-BEA was systematically characterized by XPS, XRD, DRIFTS, and UV–Vis DRS, and its acidic properties was tested by NH 3 -TPD and pyridine-adsorbed DRIFTS. We found that the hierarchical structure of HR-Zr-BEA could expose more amount of acid sites and then promote the selective conversion of xylose to the active intermediates, resulting in a higher yield of lactic acid (LaA) from xylose. Besides, HR-Zr-BEA also exhibited excellent reusability and substrate-generality. The hierarchical HR-Zr-BEA catalyst prepared via an alkali etching-free method exposes more amount of accessible acid sites and then enhances the production of lactic acid from carbohydrates under the mild reaction conditions. [Display omitted] • A hierarchical HR-Zr-BEA catalyst is constructed via alkali etching-free process. • HR-Zr-BEA shows superior activities in converting carbohydrates to lactic acid. • Hierarchical structure of HR-Zr-BEA exposes more amount of accessible acid sites. • HR-Zr-BEA promotes the conversion of xylose to active intermediates. • HR-Zr-BEA also shows an excellent reusability and substrate-generality. [ABSTRACT FROM AUTHOR]