Production Cost and Carbon Footprint of Biomass-Derived Dimethylcyclooctane as a High-Performance Jet Fuel Blendstock

Abstract

Near-term decarbonization of aviation requires energy-dense, renewable liquid fuels. Biomass-derived 1,4-dimethylcyclooctane (DMCO), a cyclic alkane with a volumetric net heat of combustion up to 9.2% higher than Jet A, has the potential to serve as a low-carbon, high-performance jet fuel blendstock that may enable paraffinic bio-jet fuels to operate without aromatic compounds. DMCO can be produced from bio-derived isoprenol (3-methyl-3buten-1-ol) through a multistep upgrading process. This study presents detailed process configurations for DMCO production to estimate the minimum selling price and life-cycle greenhouse gas (GHG) footprint considering three different hydrogenation catalysts and two bioconversion pathways. The platinum-based catalyst offers the lowest production cost and GHG footprint of $9.0/L-Jet-A eq and 61.4 gCO 2e /MJ, given the current state of technology. However, when the supply chain and process are optimized, hydrogenation with a Raney nickel catalyst is preferable, resulting in a $1.5/L-Jet-A eq cost and 18.3 gCO 2e /MJ GHG footprint if biomass sorghum is the feedstock. This price point requires dramatic improvements, including 28 metric-ton/ha sorghum yield and 95−98% of the theoretical maximum conversion of biomass-to-sugars, sugars-to-isoprenol, isoprenol-to-isoprene, and isoprene-to-DMCO. Because increased gravimetric energy density of jet fuels translates to reduced aircraft weight, DMCO also has the potential to improve aircraft efficiency, particularly on long-haul flights.

Thermal cyclodimerization of isoprene for the production of high-performance sustainable aviation fuel

“…Therefore, nickel-based catalysts are likely preferred for the hydrogenation of the isoprene cyclodimers. 51 However, the higher pressures and temperatures required to obtain complete conversion may partially offset the lower catalyst cost.…”

Life-Cycle Greenhouse Gas Emissions of Sustainable Aviation Fuel through a Net-Zero Carbon Biofuel Plant Design

“…The CI of SAF derived from corn grain ethanol is 26% lower than the CI of petroleum jet fuel, and several cellulosic and advanced biomass feedstock have potential emission reductions of 33%–91% . For that reason, many previous studies have focused on developing the cellulosic pathways to SAF production. − …”

A Combined Photobiological-Photochemical Route to C10 Cycloalkane Jet Fuels from Carbon Dioxide via Isoprene

“…26,27 Interestingly, the hydrogenated [4+4] dimers of isoprene have better fuel properties compared to conventional jet fuels (Jet-A), and a life-cycle assessment and technoeconomic analysis showed that the process can be further improved to reduce cost and emission to compete within the sustainable aviation fuel sector. 28 The [2+2] oligomerization of isoprene was not selective for dimers since also trimers and tetramers were formed in significant amounts.…”