Elucidating the Influence of Functional Groups on Reaction Pathway During Selective Hydrodeoxygenation of Lignin Model Compounds

Abstract In the transition toward a sustainable circular economy, the urgent demand for clean and renewable energy solution has become increasingly evident. Catalytic conversion of biomass has emerged as a particularly promising strategy to meet this challenge, owing to the abundant availability and widespread accessibility of biomass resources. This study focuses on the typical lignin phenolic model compounds, specifically anisole, guaiacol, and 4‐propylguaiacol, which constitute the primary components of lignin oil. These compounds are investigated and transformed into liquid hydrocarbons through the hydrodeoxygenation (HDO) reaction using the Ru/Al 2 O 3 catalyst. The catalyst demonstrates high activity in catalyzing the HDO of these model compounds, individually, with a 100% selectivity of liquid hydrocarbons (C x H y ). When the three compounds are mixed as a mimic lignin oil, roughly 10% of 1‐methoxy cyclohexane remains and cannot be converted to hydrocarbons. The reactivity of each functional group of the phenolic compounds and the side chain influences on the C aryl − OCH 3 and C aryl − OH bonds cleavage, and direct hydrogenation reaction is also investigated by comparing the reaction rates via the kinetic studies. The discoveries presented in this work are expected to inspire advancements in biomass conversion and biofuel upgrading, particularly through HDO reactions under mild conditions.