Selective hydrogenation of reducing sugars over SiO2@Ni/NiO hetero-structured nanoreactor in Mg-driven aqueous phase

Abstract

Selective hydrogenation is of growing interest in biomass upgrading to be performed over non-precious metal-based catalyst in aqueous phase. Herein, a nickel/nickel oxide hetero-structural catalyst to reducing sugars hydrogenation is designed based on the tailored interfacial synergy and structural composition. Such synergistic silica @ nickel/nickel oxide (SiO2@Ni/NiO) with core–shell structure features in i) interconnected tubes on the shell offering spatial restriction to hydrogen attraction and reactant diffusion, ii) hetero-interfaced Ni/NiO shell balancing the H2 and glucose adsorption chemically, iii) the core shell catalyst providing nano-reactor for reactant enrichment, furthering improving the utilization of nickel active sites. Furthermore, the high solubility of in-situ generated H2 driven by Mg in this aqueous phase hydrogenation system greatly assist the interaction among the reactants. The SiO2@Ni/NiO catalyst exhibits high activity in glucose hydrogenation, under which the conversion rate and sorbitol selectivity can achieve 99 % and 90 % under mild condition of 393 K for 3 h, respectively. It also shows remarkable reuse ability and wide application scope to sugars hydrogenation in this in-situ hydrogen generation process. This proposal gains insights to cooperative catalyst design on chemical composition and nanostructure for advancing biomass-based sugars hydrogenation process.