High-Density Biosynthetic Fuels: The Intersection of Heterogeneous Catalysis and Metabolic Engineering
Benjamin G. Harvey, Heather A. Meylemans, Raina V. Gough, Roxanne L. Quintana, Michael Garrison, Thomas J. Bruno
Biosynthetic valencene, premnaspirodiene, and natural caryophyllene were hydrogenated and evaluated as high performance fuels. The parent sesquiterpenes were then isomerized to complex mixtures of hydrocarbons with the heterogeneous acid catalyst Nafion SAC-13. High density fuels with net heats of combustion ranging from 133-141,000 btu/gal, or up to 13% higher than commercial jet fuel could be generated by this approach. The products of caryophyllene isomerization were primarily tricyclic hydrocarbons which after hydrogenation increased the fuel density by 6%. The isomerization of valencene and premnaspirodiene also generated a variety of sesquiterpenes, but in both cases the dominant product was δ-selinene. Ab initio calculations were conducted to determine the zero point vibrational energies for the reactants and products. In all cases the results were in excellent agreement with the experimental distribution of isomers. The cetane numbers for the sesquiterpane fuels ranged from 20-32 and were highly dependent on the isomer distribution. Specific distillation cuts may have the potential to act as high density diesel fuels, while use of these hydrocarbons as additives to jet fuel has the potential to increase the range and/or time of flight of aircraft. In addition to the ability to generate high performance renewable fuels, the powerful combination of biosynthesis and heterogeneous catalysis allows for the preparation of a variety of unique sesquiterpenes with potential for pharmaceutical, flavor, and fragrance applications.
, Meylemans, H.
, Gough, R.
, Quintana, R.
, Garrison, M.
and Bruno, T.
High-Density Biosynthetic Fuels: The Intersection of Heterogeneous Catalysis and Metabolic Engineering, Physical Chemistry Chemical Physics, [online], https://doi.org/10.1039/C3CP55349C
(Accessed November 29, 2023)