The development of efficient catalytic methods for the synthesis of bio-based, full-performance jet fuels is critical for limiting the impacts of climate change while enabling a thriving modern society. To help address this need, here, linalool, a terpene alcohol that can be produced via fermentation of biomass sugars, was dehydrated, cyclized, and hydrogenated in a one-pot reaction under moderate reaction conditions. This sequence produced a biosynthetic fuel mixture primarily composed of 1-methyl-4-isopropylcyclohexane (p-menthane) and 2,6-dimethyloctane (DMO). The reaction was promoted by a catalyst composed of commercial Amberlyst-15, H+ form, and 10% Pd/C. Two other terpenoid substrates (1,8-cineole and 1,4-cineole) were subjected to the same conditions and excellent conversion to high purity p-menthane was observed. The fuel mixture derived from linalool exhibits a 1.7% higher gravimetric heat of combustion and 66% lower kinematic viscosity at −20 °C compared to the limits for conventional jet fuel. These properties suggest that isomerized hydrogenated linalool (IHL) can be blended with conventional jet fuel or synthetic paraffinic kerosenes to deliver high-performance sustainable aviation fuels for commercial and military applications.

Isoprene was hydrovinylated with a series of α-olefins (1-pentene, 1-hexene, 1-heptene, 1-octene) to produce acyclic branched C 10 −C 13 alkenes. The process utilized CoBr 2 (DPPE) as the precatalyst in loadings as low as 0.1 mol % and zinc as the reducing agent. Use of the cobalt catalyst resulted in primarily 1,4-addition, with carbon coupling at the 4-position of isoprene. A significant amount (∼20%) of the coupling products at the 1-position of isoprene was also observed. Each of the discrete C 10 , C 11 , C 12 , and C 13 products were then hydrogenated with 10% Pd/C (200 °C; 650 psi H 2 ) to yield jet fuel blendstocks. In addition to the reactions with pure α-olefins, an equimolar mixture of the C 5 −C 8 α-olefins was used to mimic a stream of olefins produced from ethanol dehydration/oligomerization or Fischer−Tropsch catalysis. The different fuel blends exhibited densities ranging from 0.73 to 0.76 g mL −1 , gravimetric net heats of combustion (NHOC) from 43.91 to 44.13 MJ kg −1 , and −20 °C kinematic viscosities from 2.4 to 6.3 mm 2 s −1 . The NHOC values were ∼2.9% higher than the lower limit for Jet-A, while the low-temperature viscosities were up to 70% lower than the upper limit for Jet-A. In addition to studying the suitability of the lightly branched hydrocarbons generated in this process as jet fuel blendstocks, it was of interest to explore their potential as diesel fuels. The equimolar C 10 −C 13 fuel mixture exhibited a derived cetane number (DCN) of 56, which is 16 units higher than that required for Diesel #2 (40). The outstanding fuel properties of the isoprene-derived fuels suggest that they have applications as replacements for both petroleum-derived Jet-A and Diesel #2.

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