Synthesis of polycyclic High-Density jet fuel from β-Pinene and Lignocellulose-Derived aromatic aldehydes

With the intensification of global energy crises and environmental issues, the development of sustainable, high-energy–density aviation fuels has become a prominent research focus. This study constructs polycyclic high-energy–density aviation fuels using β-pinene and lignocellulose-derived furfural/benzaldehyde as feedstocks through oxidation, aldol condensation, and hydrodeoxygenation reactions. Initially, β-pinene was efficiently oxidized by potassium permanganate to nopinone (achieving 99.2 % conversion with 91.5 % selectivity). Subsequently, nopinone underwent aldol condensation with aromatic aldehydes under solid base catalysts to obtain unsaturated ketone intermediates with high selectivity. Experimental results demonstrated that MgO exhibited optimal catalytic performance (96 % conversion for benzaldehyde condensation, 95 % for furfural condensation), with catalytic activity correlating to catalyst basicity and reaction temperature. The condensation products were successfully converted into polycyclic alkanes through hydrodeoxygenation (HDO) using Pd/C and Hβ catalysts synergistically. Density Functional Theory (DFT) calculations elucidated the regulatory mechanism of aldehyde LUMO energy level differences on reactivity, clarified the energy variations during hydrodeoxygenation, and proposed plausible reaction pathways. The final products exhibited densities of 0.891 and 0.916 g·cm −3 (20°C) with corresponding heating values of 45.18 and 46.81 MJ·kg −1 , respectively, along with a freezing point as low as −64.1°C, demonstrating performance metrics closely approaching those of commercial JP-10 fuel.