Conversion of lignin oil and hemicellulose derivative into high-density jet fuel

Synthesizing high-density fuel from lignocellulose can not only achieve green and low-carbon development, but also expand the feedstock source of hydrocarbon fuel. Here, we reported a route of producing high-density fuel from lignin oil and hemicellulose derivative cyclopentanol through alkylation and hydrodeoxygenation. HY with SiO2/Al2O3 molar ratio of 5.3 was screened as the alkylation catalyst in the reaction of model phenolic compounds and mixtures, and the reaction conditions were optimized to achieve conversion of phenolic compounds higher than 87% and selectivity of bicyclic and tricyclic products higher than 99%. Then two phenolic pools simulating the composition of two typic lignin oils were studied to validate the alkylation and analyze the competition mechanism of phenolic compounds in mixture system. Finally, real lignin oil from depolymerized of beech powder was tested, and notably 80% of phenolic monomers in the oil were converted into fuel precursor. After hydrodeoxygenation, the alkylated product was converted to fuel blend with a density of 0.91 g/mL at 20 °C and a freezing point lower than −60 °C, very promising as high density fuel. This work provides a facile and energy-efficient way of synthesizing high-performance jet fuel directly from lignocellulosic derivatives, which decreases processing energy consumption and improve the utilization rate of feedstock.