Synthesis of jet fuel with high heat-sink and low freezing-point via alkylation of phenol with ethanol and subsequent hydrodeoxygenation

The synthesis of high-performance jet fuel from biomass presents a solution to energy crises and environmental pollution. This paper introduces a novel strategy for producing jet fuel with a high heat sink and low freezing point using bio-derived phenol and ethanol. The production route comprises two successive steps: the alkylation of phenol with ethanol, followed by hydrodeoxygenation (HDO), catalyzed by Hβ zeolite and Pt/C, respectively. The alkylation conditions were optimized at 260 °C for 8 h, achieving phenol conversion rates exceeding 95 % and yielding 88.7 % alkylphenol at a phenol to ethanol molar ratio of 1:3. The final HDO products consisted of 20.25 % monoethylcyclohexane, 44.87 % diethylcyclohexane, and 28.32 % triethylcyclohexane. These products demonstrated a heat sink capacity of 3.3 MJ/kg, a freezing point below −65 °C, a heat value of 45.4 MJ/kg, and a density of 0.82 g/cm 3 at 20 °C, surpassing the performance metrics of conventional JP-8 fuel. Kinetic studies on the alkylation revealed activation energies of 58.36 kJ/mol for O-alkylation and 122.07 kJ/mol for C-alkylation. The findings contribute to understanding the mechanisms of alkylation reactions between phenolic compounds and short chain alcohols. This work offers a straightforward and energy-efficient way to synthesize high-performance jet fuel from lignocellulosic derivatives, reducing processing energy consumption and enhancing feedstock utilization rates.