Bio-oil from renewable biomass pyrolysis holds great potential as a feedstock for upgrading into biofuels and value-added chemicals. However, its water-insoluble fraction presents challenges for upgrading due to its high molecular weight, compositional complexity, and tendency to coke under heat, often requiring harsh conditions and facing catalyst deactivation. Here, we report a mild and efficient electrochemical conversion system tailored for the bio-oil–water-insoluble fraction. By integrating methanol-assisted hydrogen-transfer and metal nanoparticle synergistic catalysis, we suppressed competitive reactions and promoted the diffusion and hydrogenation of the water-insoluble components, enabling their conversion into hydrocarbon fuels under ambient conditions. At a current density of 100 mA cm–2, the system achieved a peak Faradaic efficiency of 21.30% within the first 30 min, while hydrocarbons accounted for over 98% of the products detected by gas chromatography–mass spectrometer. The catalytic performance of the system remained stable within 7 cycles, and the recovery rate of the catalyst exceeded 94%. Combined experimental and theoretical insights elucidate the competitive reactions among the water-insoluble fraction. This work represents an important step toward the mild and efficient full-fraction conversion of bio-oil and its practical utilization.
Lv et al. (Sat,) studied this question.