Multiple active sites of CuO/CeO2 catalysts toward enhanced hydrogenolysis of hardwood lignin into phenolic monomers

Abstract

Reductive catalytic deconstruction (RCD) is a promising strategy for achieving high-value added utilization of lignocellulose. Herein, we report a CuO/CeO₂ catalyst with multiple active sites for effective RCD lignocellulose into phenolic compounds, affording monomer yields up to 41.9 wt%. Notably, this fabricated catalyst achieves rapidly hydrogenolysis of hardwood lignin with yields of 32.7 wt% within 1 h. The enhanced catalytic reactivity is obtained by the efficient C–O bond scission, which is confirmed by the nuclear magnetic resonance spectra and examination of lignin model compound reactions. Moreover, the resultant CuO/CeO₂ catalyst reveals relatively stability under a H₂ atmosphere duo to the strong interactions between nanorods CeO₂ and Cu. The effects of key parameters, such as time, temperature and solvent, were investigated by monomeric yields. This work provides new insights into lignin first strategy and paves the way for the rational design of non-precious metal catalysts with multiple-active sites.