Hydrodeoxygenation (HDO) plays a crucial role in upgrading pyrolysis-oil derived from biomass. Here we describe a method for fabricating a carbon-encapsulated nickel metal–acid bifunctional catalyst (Ni@C/RCS-Al) supported on aluminum-doped radial channel silica (RCS-Al). This catalyst exhibits a large surface area and highly dispersed accessible active sites, achieved through a combination of salicylate- and MOF-assisted strategies. The RCS-Al was prepared by a one-pot salicylate-assisted hydrothermal method in an aqueous phase containing an Al source, which is simple, has a high yield, and saves time. The results show that Ni@C/RCS-Al displays a well-defined radial channel pore structure with a mesopore diameter of 31.1 nm, which can significantly increase the number of accessible active sites and accelerate mass transfer. The MOF-assisted strategy leads to the formation of highly dispersed smaller carbon-encapsulated nickel nanoparticle active sites, and Al doping contributes to the adjustable acid sites, demonstrating that Ni@C/RCS-Al is a metal–acid bifunctional catalyst. Importantly, the kinetics study revealed a high reaction constant for the constructed Ni@C/RCS-Al catalyst. Ni@C/RCS-Al demonstrates remarkable performance in HDO, achieving complete m-cresol conversion and 100 % selectivity to the target product methylcyclohexane within a brief period of 75 min (T = 250 °C p = 2 MPa, m-cresol/catalyst (g) = 7.5). This exceptional performance stems from its radial channel pore structure and optimization of metal–acid sites. The thin carbon layer on the Ni surface contributes to its superior stability and water resistance, as verified by an experimental study and DFT calculations. This work opens up a new idea for the application of radial channel silica-supported catalysts in various reactions.
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