Aqueous Hydrogenation of Rosin Catalyzed by Amphiphilic Ni–Cu Nanocatalysts

Abstract

An amphiphilic mesoporous silica-coated N-doped hollow mesoporous carbon spherical nanomaterial (N-HMC@MS) with a large pore diameter and high nitrogen content has been successfully prepared using a typical emulsion-induced interface assembly strategy and a high-temperature limited carbonization method. To solve the problem of easy aggregation of Ni nanoparticles and improve their catalytic activity, bimetallic amphiphilic Ni-based catalysts (Ni–Cu/N-HMC@MS) were prepared by loading Ni and Cu nanoparticles on N-HMC@MS by the impregnation-hydrogen reduction method. The catalysts were fully characterized and applied to the hydrogenation of rosin macromolecules. The larger pore size of the catalysts makes mass transfer more convenient, and the doped nitrogen elements in the material can provide more coordination anchoring sites for metal nanoparticles. Amphiphilicity can not only improve the dispersion of catalysts in water but also increase the affinity for organic reaction substrates, which can realize effective green catalysis in aqueous medium. Nonprecious metal Ni as the active component greatly reduces the production cost. The influence of various reaction conditions on the catalytic reaction was investigated, and the best reaction process was selected. The catalyst Ni₅–Cu₁/N-HMC@MS shows good activity and high stability, which can be compared with precious metal catalysts Pd and Ru. This study points out an environmentally friendly direction for the further processing and exploitation of rosin resources and brings an idea for the development of aqueous catalytic hydrogenation with nonprecious metal catalysts.