Three biorenewable monoterpenes, α-pinene, limonene, and sabinene, were hydrogenated to generate cycloalkane blendstocks. The saturated terpenes, along with the high density multicyclic fuels JP-10 and RJ-4, were then blended with three different synthetic paraffinic kerosenes (SPKs) in various proportions. The SPKs consisted of HEFA-Jet (a complex mixture of acyclic hydrocarbons generated by hydrotreatment of fatty acids and esters), 5-methylundecane (5-MU, a C 12 hydrocarbon that can be generated from bioethanol), and DMO (a C 10 branched chain hydrocarbon that can be derived from acyclic monoterpenes, including myrcene and linalool). Blends were limited to <50% cycloalkane by volume with a focus on fuels combining densities higher than the minimum requirement for Jet-A (>0.775 g mL -1 ), −40 °C kinematic viscosities <12.0 mm 2 s −1 , and gravimetric net heats of combustion (NHOCs) > 42.80 MJ kg -1 . Through this approach, high-performance jet fuels with gravimetric NHOCs of up to 43.68 MJ kg -1 (2.1% higher than the lower limit for Jet-A) or volumetric NHOCs of up to 36.05 MJ L -1 (8.7% higher than the lower limit for Jet-A) could be produced. These biobased, zero-aromatic jet fuels have the potential to deliver enhanced performance compared to Jet-A, while reducing the environmental impact of commercial and military aviation.

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The sustainable, bio-based, platform chemical, 2,5-hexanedione [HD (1)], was efficiently converted to methylcyclopentadiene [MCPD (4)] through a three-step process consisting of intramolecular aldol condensation, catalytic chemoselective hydrogenation, and dehydration. Base-catalyzed aldol condensation of 1 resulted in the formation of 3-methyl-2-cyclopenten-1-one [MCO (2)], which was then converted to 3-methyl-2-cyclopenten-1-ol [MCP (3)] by chemoselective reduction with a ternary Ru catalyst system [RuCl 2 (PPh 3) 3 /NH 2 (CH 2) 2 NH 2 /KOH]. The hydrogenation proceeded with 96 % chemoselectivity. 3 was then dehydrated over AlPO 4 /MgSO 4 at 70°C under reduced pressure to yield 4, which can undergo an ambient temperature [4 + 2]-Diels-Alder cyclization to generate dimethyldicyclopentadiene (DMDCPD), a commodity chemical useful for the preparation of high-performance fuels and polymers. Through this approach, advanced jet fuels and materials can be conveniently produced from sustainable cellulosic feedstocks.