Liquid-phase hydrodeoxygenation (HDO), catalyzed by metal or metal-acid sites, provides an effective catalytic strategy to remove oxygen-containing functionalities of lignin-derived phenolic compounds on the route to fuels and chemicals. Developing the catalyst with high activity and stability is crucial for such a chemical process but still remains a significant challenge. In this contribution, highly dispersed subnanometric Ru metal clusters (<1.5 nm) encapsulated in the cavities of MWW zeolites, including HMCM-22 and its siliceous analog ITQ-1, have been developed for the HDO of guaiacol, an important lignin-derived phenolic monomer, in an apolar liquid phase under mild conditions (160 °C, 3 MPa H 2 ). We validate the effective encapsulation of Ru metal clusters in ITQ-1 and HMCM-22 zeolite cavities via complementary characterization methods. The detailed reaction pathways of the HDO of guaiacol are depicted by using guaiacol, phenol, and anisole as reactants. The subnanometric Ru metal clusters confined in MWW zeolite thin layers (20−30 nm in thickness) show remarkable enhancement in HDO activity compared to the large metal particles. The close proximity between Ru metal clusters and Brønsted acid sites (BAS) confined in zeolite constraints delivers a synergistic effect, leading to an additional enhancement in catalytic activity as well as product selectivity. The super stability of the ultrafine Ru metal clusters against sintering and leaching after successive catalytic runs is achieved. The welldefined mono-or bifunctional Ru-containing MWW zeolite catalysts enable the fundamental understanding of HDO of ligninderived phenolic compounds in the apolar liquid phase and also provide a prototype for the design of superior catalysts for other energy-related transformations.

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Hierarchical zeolites have attracted great attention due to the integration of mesopores and/or macropores into the microporous crystalline framework, which decreases the steric and diffusional limitations in the small-size micropores of zeolites. Among them, single-crystalline hierarchical zeolites are much desirable due to fewer crystalline defects, higher mechanical stability, and less blocking of the uniform direction of microporous channels, which show high catalytic performance in conventional industrially-important small-molecule reactions, and heavy-oil catalytic cracking, biomass catalytic conversion, polymer degradation, etc. Here, a novel one-pot kineticsdominated strategy was developed to synthesize titaniumcontaining single-crystalline hierarchical zeolites via synergy of polyelectrolytes and framework hetero-atoms by means of concentrating the starting precursor, restriction of the Oswald ripening to protect nano-crystals, as well as oriented attachment between nano-crystals. The resultant zeolite displayed a much higher catalytic performance in olefin epoxidation and cyclohexanone ammoximation than those of conventional pure-microporous zeolites.Zeolites are microporous crystalline solid materials with high surface area and high thermal/hydrothermal stability, which are widely used as solid catalysts in refining and petrochemical processes. [1] The intrinsic micropores (< 2.0 nm) at the level of molecular size gave zeolites remarkable catalytic properties over other catalysts, especially their unique shape-selectivity. [2] [a] Y.