One-pot conversion of lignocellulosic biomass to ketones and aromatics over a multifunctional Cu–Ru/ZSM-5 catalyst

The complete conversion of lignocellulosic biomass to selective and highly valuable chemicals is challenging because of its inertness and complexity. Herein, we report a direct chemocatalytic route for the complete one-pot conversion of raw woody biomass to cyclic ketones and aromatic monomers over a multifunctional bi-metallic Cu–Ru catalyst on HZSM-5 (Cu–Ru/Z). The Si/Al ratio of HZSM-5 plays an effective role in the product distribution. High-yield ketones (60.9% based on carbon in holocellulose) and aromatics (28.4% based on carbon in lignin) were produced in an aqueous medium. Three strategies, metal domain encapsulation inside the zeolitic framework, SiO 2 layer coating, and carbon layer coating, were employed to overcome the weak hydrothermal stability associated with HZSM-5. The carbon-coated Cu–Ru/Z catalyst exhibited high stability up to three reaction cycles. Optimization of the reaction conditions, reaction mechanisms for the selective ketone synthesis, and catalyst deactivation mechanisms are discussed. • One-pot chemocatalytic conversion of wood to value-added chemicals. • Multifunctional Cu–Ru/HZSM-5 produced 60.9 C% ketones and 28.4 C% aromatics. • Adsorption of lignin oligomers on catalyst favored the formation of cyclic ketones. • Carbon coating on Cu–Ru/HZSM-5 increased its hydrothermal stability.