An initial economic assessment of the process has indicated the technology could produce ethanol at a cost savings of roughly 10 percent when compared with current state-of-the-art technologies.

MADISON, Wis. - Using a plant-derived chemical, University of

Wisconsin-Madison researchers have developed a process for creating a
concentrated stream of sugars that's ripe with possibility for biofuels.

"With the sugar platform, you have possibilities," says Jeremy Luterbacher,
a UW-Madison postdoctoral researcher and the paper's lead author. "You've
taken fewer forks down the conversion road, which leaves you with more end
destinations, such as cellulosic ethanol and drop-in biofuels."

Funded by the National Science Foundation and the U.S. Department of
Energy's Great Lakes Bioenergy Research Center (GLBRC), the research team
has published its findings in the Jan. 17, 2014 issue of the journal
Science, explaining how they use gamma valerolactone, or GVL, to deconstruct
plants and produce sugars that can be chemically or biologically upgraded
into biofuels. With support from the Wisconsin Alumni Research Foundation
(WARF), the team will begin scaling up the process later this year.

Because GVL is created from the plant material, it's both renewable and more
affordable than conversion methods requiring expensive chemicals or enzymes.
The process also converts 85 to 95 percent of the starting material to
sugars that can be fed to yeast for fermentation into ethanol, or chemically
upgraded furans to create drop-in biofuels.

To demonstrate the economic viability of this advance, Luterbacher needed to
concentrate the sugar, remove the GVL for reuse, and show that yeast could
successfully generate ethanol from the sugar stream.

"Showing that removing and recycling GVL can be done easily, with a
low-energy separation step, is a little more of an achievement," says
Luterbacher. "By feeding the resulting sugar solution to microorganisms, we
proved we weren't producing some weird chemical byproducts that would kill
the yeast, and that we were taking out enough GVL to make it nontoxic."

"What's neat is that we can use additives to make the solution separate,"
says Luterbacher. "It becomes like oil and vinegar."

Their additive of choice: liquid carbon dioxide.

"It's green, nontoxic and can be removed by simple depressurization once you
want GVL and solutions of sugar to mix again. It's the perfect additive,"
Luterbacher says.

An initial economic assessment of the process has indicated the technology
could produce ethanol at a cost savings of roughly 10 percent when compared
with current state-of-the-art technologies.

For the past several years, James Dumesic, Steenbock Professor and Michel
Boudart Professor of Chemical and Biological Engineering at UW-Madison, and
his research group have studied the production of GVL from biomass, and in
more recent work they explored the use of GVL as a solvent for the
conversion of biomass to furan chemicals.

"The knowledge gained in these previous studies was invaluable to us in the
implementation of our new approach to convert real biomass to aqueous
solutions of sugars that are suitable for biological conversion," says
Dumesic.

This research has contributed new knowledge to the biofuels landscape,
resulted in four patent applications, and gained recognition for GVL's
commercial potential from WARF's Accelerator Program. The program helps
license high potential technologies more rapidly by addressing specific
technical hurdles with targeted funding and expert advice from seasoned
business mentors in related fields.

Under the Accelerator Program effort, Dumesic will serve as principal
investigator for an 18-month project involving construction of a
high-efficiency biomass reactor. The reactor will use GVL to produce
concentrated streams of high-value sugars and intact lignin solids.

Carbohydrates and lignin from the reactor will be delivered to scientific
collaborators, including fellow GLBRC investigators, who will optimize
strategies for converting the materials into valuable chemicals and fuels.

"We're excited by the team's scientific achievements and we look forward to
supporting the project's next steps through the Accelerator Program," says
Leigh Cagan, WARF's chief technology commercialization officer. "If the
project successfully achieves the anticipated cost reductions for production
of the sugars, lignin and ethanol, we anticipate significant commercial
interest in this novel process."

For more information on the GVL technologies, contact licensing@warf.org.