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Final Up to date on: third Might 2025, 12:12 am
Patent-Pending Expertise Turns Lignin—a Plant Structural Materials—Into Fragrant Hydrocarbons That May Assist Leap Over Artificial Aviation Gasoline ‘Blend Wall’
It is a perfect complement to Comstock Fuels’ personal applied sciences: an extra refining step to improve lignin from biomass into fragrant hydrocarbons, that are molecules wanted to supply “drop-in” artificial aviation gas (SAF).
SAF could be made with ample biomass and waste sources from America’s farms, forests, and waste services. Nonetheless, most SAF right this moment should be mixed with petroleum jet gas (Jet A) to fulfill strict efficiency necessities for aviation. It is because jet engines want gas that comprises a mix of hydrocarbons for protected operation—alkanes (together with n-alkanes, isoalkanes, and cycloalkanes) and aromatics. To this point, most SAF manufacturing processes yield fuels wealthy in n-alkanes and isoalkanes, however pathways for producing aromatics and cycloalkanes are scarce.
However the SAF know-how being codeveloped by the Massachusetts Institute of Expertise (MIT) and the Nationwide Renewable Power Laboratory (NREL) is totally different. It yields aromatic-rich SAF by deconstructing lignin in vegetation and hydrodeoxygenating the ensuing molecules to jet-range blendstocks.
Understanding that SAF must comprise roughly 20% aromatics, Comstock Fuels President David Winsness jumped on the chance to scale up the know-how. In September 2024, Comstock Fuels signed a cooperative analysis and growth settlement with MIT and NREL.
If the MIT–NREL know-how is efficiently scaled up and built-in into Comstock’s present processes, the mixture of applied sciences might assist tackle the so-called SAF “blend wall”—offering a path towards SAF that’s functionally an identical to Jet A.
A Likelihood Encounter Sparks Analysis Settlement
Winsness found the patent-pending MIT–NREL lignin conversion know-how throughout an exploratory assembly at NREL’s Golden, Colorado, campus, the place he was discussing scaling up Comstock’s Bioleum SAF know-how. Throughout that assembly, NREL Principal Scientist Robert Baldwin launched Winsness and his colleagues to the brand new lignin pathway and really helpful an introduction to NREL Senior Analysis Fellow Gregg Beckham and NREL chemical engineer and group supervisor David Brandnerwho collectively lead NREL’s part of the work with a crew of researchers.
A veteran of the biofuels trade, Winsness had himself developed and commercialized a patented course of that recovers distillers corn oil from corn ethanol services to be used in producing further fuels, rising yields and revenues. Upward of 95% of the U.S. corn ethanol trade makes use of the know-how right this moment. Winsness and his crew then set their sights on lignin as their subsequent innovation on the assumption that doing so might assist petroleum, pulp and paper, forestry, and different related industries.
After greater than 10 years, they developed a patented and patent-pending course of that extracts and converts lignin into an intermediate known as Bioleum. In an August 2024 press launch, the corporate reported yields of cellulosic ethanol and Bioleum-derived fuels exceeding 125 gallons per metric ton of biomass (on a gasoline-gallon-equivalent foundation), relying on feedstock, lignin content material, website situations, and different course of parameters.
After Baldwin’s preliminary introduction to Beckham and a collection of follow-up communications, it turned clear that the MIT–NREL lignin-based SAF know-how might complement Comstock’s processes by refining Bioleum additional to supply each alkane and fragrant SAF. The events not too long ago executed an unique license settlement, along with the analysis settlement, simply six months after their first assembly.
At its pilot facility in Wisconsin, Comstock Fuels is at present scaling up and demonstrating its Bioleum know-how to transform woody biomass into SAF. One step of Comstock’s chemical processes isolates lignin by separating it from the opposite main plant polymers—the polysaccharides cellulose and hemicellulose—which proceed by the method for conversion into alkane SAF.
“The type of digestion we are already doing is ideal for MIT and NREL’s technology,” Winsness mentioned.
It was there—the place Comstock produces a stream of lignin—that Baldwin and Winsness noticed an thrilling interdependency and linkage level.
“MIT and NREL’s technology makes a highly aromatic blendstock, but that’s great because most of the other SAF technologies out there today make blendstocks that don’t contain aromatics,” Baldwin mentioned. “To get 100% SAF, you have to have some source of aromatics, and one way to get them is from lignin.”
From Lignin to Extremely Fragrant SAF
Lignin—which makes up round 30% of biomass—is a fancy polymer that helps vegetation and helps them resist decay. Based mostly on projections of future feedstock provide, that are outlined within the U.S. Department of Energy’s 2023 Billion-Ton Reportlignin might generate as a lot as 63 billion gallons of SAF yearly by 2040—3 times extra gas than U.S. airways consumed in 2019.
Nonetheless, for years the trade has lacked the important thing for unlocking that potential. Researchers proceed to seek for economical strategies for turning lignin into helpful merchandise, together with the fragrant hydrocarbons wanted for SAF. Within the pulp and paper trade right this moment, lignin is burned for warmth, although NREL and different researchers are additionally growing technologies for turning waste lignin into valuable bioproducts.
Nonetheless, constructing on advances in catalysis, a multi-institution crew of researchers, together with MIT’s Mickey Stone, Matt Webber, and Yuriy Román-Leshkov, unveiled a examine with the potential to overturn that dynamic. With assist from the U.S. Division of Power’s Bioenergy Applied sciences Workplace, they demonstrated a way for eradicating oxygen from lignin and a catalyst to refashion the ensuing molecules into an aromatic-rich SAF blendstock—an additive for mixing with alkane SAF.
First described in a 2022 Joule articlethe know-how combines alcohol extraction of lignin from biomass with an Earth-abundant hydrodeoxygenation catalyst to stabilize the extracted lignin and produce an oil enriched with aromatics. Importantly, this catalyst resists deactivation or poisoning from impurities usually current in biomass.
Having efficiently demonstrated the know-how within the lab, MIT and NREL filed a patent software for the know-how. Now, to indicate its worth outdoors the lab for the biofuels trade, it’s time to scale it up.
The Three-12 months Plan: Scaling It Up
Over the following three years, Comstock will construct a pilot-scale model of the MIT–NREL lignin conversion know-how, a activity that entails linking the varied steps into an uninterrupted course of that may run constantly. They can even incorporate bigger reactors and tools, transferring from producing milliliters of the fragrant SAF blendstock to some gallons.
That course of will present Comstock with useful knowledge and engineering designs to contemplate as it really works to combine it with its personal Bioleum know-how. Winsness mentioned that the MIT–NREL course of could be added with a couple of minor modifications to simply accept the present lignin stream.
“We already have over 2,000 runs on our pilot reactor and a tremendous amount of data,” Winsness mentioned. “We think we can take the MIT–NREL process from a technology readiness level (TRL) of 4 to 6 very quickly if all goes well.”
After all, that will not be the top of the systematic course of for demonstrating and commercializing the know-how. After efficiently piloting the MIT–NREL course of at TRL 6 and seven, Comstock would then have to combine the method into even bigger services within the coming years, elevating the Comstock and MIT–NREL processes to TRL 8 and 9. Comstock Fuels plans to license the applied sciences globally and to construct, personal, and function its personal community of Bioleum refineries in the US with a number of websites beneath analysis for building of its preliminary demonstration-scale facility—paving the best way for commercialization.
Success might put thousands and thousands of extra gallons of SAF into {the marketplace}, based on NREL senior licensing government Eric Payne.
“It’s not every day the lab gets a partner like Comstock who’s ready to jump in and fund technology scale-up, which is so critical for commercialization,” he mentioned. “They’ve got the potential to impact billions of gallons of SAF, and that is really exciting. This is a huge market.”
Be taught extra about NREL’s biofuels and bio-based chemicals researchin addition to the laboratory’s broader advanced aviation research.
By Erik Ringle. Article from NREL.
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