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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]

Efficient production of high value-added chemicals and biofuels via low-temperature chemoselective HDO of lignin derivatives in water is still a challenge. Here, we construct a low-cost, active and stable Pd/PCE catalyst using phosphoric acid-modified commercial Celite (PCE) as the support, and this catalyst exhibits excellent activity in low-temperature HDO of vanillin as well as other lignin derivatives in water. The superior catalytic performance is due to the presence of P species on the surface of Pd/PCE, accelerating the selective conversion of the intermediate into the final product. Detailed experimental and mechanistic studies reveal that the rapid conversion of the intermediate to the final product proceeds via a free-radical process in an interfacial microenvironment created by intimate interacting between the P species and Pd NPs. The insights of this work provide a new low-cost catalytic system for efficient production of valuable chemicals and future biofuels from lignin derivatives. [ABSTRACT FROM AUTHOR]

Developing an efficient and stable catalyst for the aqueous hydrodeoxygenation (HDO) of lignin derivatives at ambient temperature is highly desirable. Here, a novel Pd/PHS catalyst with the hierarchical structure was facilely constructed. Taking HDO of vanillin (VAN, a typical molecule of lignin derivatives) to 2-methoxy-4-methyl phenol (MMP) as a model reaction, >99% VAN conversion and 98.2% MMP yield can be achieved over Pd/PHS at ambient temperature in a water solvent, outperforming the recent works reported in the literature. We found that the hierarchal zeolitic structure could immobilize acidic P species in Pd/PHS via trapping and hydrogen-bonding, and these P species could greatly accelerate the conversion of reaction intermediate, enhancing the yield of MMP product. Pd/PHS also showed excellent activities in HDO of other lignin derivatives. We think this work will provide a new route to guide the design of stable catalyst for the efficient aqueous HDO of lignin derivatives to high value-added chemicals and biofuels at ambient temperature. Active P species trapped and hydrogen-bond by the hierarchical zeolite structure intimately interacting with Pd NPs greatly enhance the ambient-temperature chemoselective hydrodeoxygenation of lignin derivatives in water. [Display omitted] • A novel Pd/PHS catalyst with the hierarchical structure is facilely constructed. • Pd/PHS shows superior ambient-temperature activities in HDO of lignin derivatives. • P species are stabilized via trapping and hydrogen-bonding. • Interaction between P species and Pd NPs enhances the production of products. • Pd/PHS also shows an excellent reusability and substrate-generality. [ABSTRACT FROM AUTHOR]