Solvent-free dehydration, cyclization, and hydrogenation of linalool with a dual heterogeneous catalyst system to generate a high-performance sustainable aviation fuel.

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. Sustainable aviation fuels offer the opportunity to both reduce CO2 emissions and produce fuels with superior properties to conventional petroleum-based fuels. Here, the bio-based monoterpene linalool is converted into an aviation fuel mixture primarily composed of p-menthane and 2,6-dimethyloctane at moderate temperatures and pressures using a combination of Amberlyst-15 and Pd/C catalysts. The resulting fuel is demonstrated to have a higher gravimetric heat of combustion, and a lower viscosity compared to petroleum derived Jet-A. [ABSTRACT FROM AUTHOR]