A Comprehensive Review of Catalytic Hydrodeoxygenation of Lignin-Derived Phenolics to Aromatics.

Single-ring aromatic compounds including BTX (benzene, toluene, xylene) serve as essential building blocks for high-performance fuels and specialty chemicals, with extensive applications spanning polymer synthesis, pharmaceutical manufacturing, and aviation fuel formulation. Current industrial production predominantly relies on non-renewable petrochemical feedstocks, posing the dual challenges of resource depletion and environmental sustainability. The catalytic hydrodeoxygenation (HDO) of lignin-derived phenolic substrates emerges as a technologically viable pathway for sustainable aromatic hydrocarbon synthesis, offering critical opportunities for lignin valorization and biorefinery advancement. This article reviews the relevant research on the conversion of lignin-derived phenolic compounds' HDO to benzene and aromatic hydrocarbons, systematically categorizing and summarizing the different types of catalysts and their reaction mechanisms. Furthermore, we propose a strategic framework addressing current technical bottlenecks, highlighting the necessity for the synergistic development of robust heterogeneous catalysts with tailored active sites and energy-efficient process engineering to achieve scalable biomass conversion systems.