There is enormous interest in using carbon dioxide to make hydrocarbon fuels, researchers say. Credit: Univ. of Minnesota |
Univ. of Minnesota researchers are a key
step closer to making renewable petroleum fuels using bacteria, sunlight, and
dioxide, a goal funded by a $2.2 million United States Department of Energy
grant.
Graduate student Janice
Frias made the critical step by figuring out how to use a protein to transform
fatty acids produced by the bacteria into ketones, which can be cracked to make
hydrocarbon fuels. The university is filing patents on the process.
The research is published
in the Journal of Biological Chemistry.
Frias, whose advisor was Larry Wackett, Distinguished McKnight Professor of
Biochemistry, is lead author. Other team members include organic chemist Jack
Richman, a researcher in the College
of Biological Sciences’ Department of
Biochemistry, Molecular Biology and Biophysics, and undergraduate Jasmine
Erickson, a junior in the College
of Biological Sciences.
Wackett, who is senior author, is a faculty member in the College of Biological Sciences
and the university’s BioTechnology Institute.
“Janice Frias is a very
capable and hard-working young scientist,” Wackett says. “She exemplifies the
valuable role graduate students play at a public research university.”
Aditya Bhan and Lanny
Schmidt, chemical engineering professors in the College of Science
and Engineering, are turning the ketones into diesel fuel using catalytic
technology they have developed. The ability to produce ketones opens the door
to making petroleum-like hydrocarbon fuels using only bacteria, sunlight and
carbon dioxide.
“There is enormous
interest in using carbon dioxide to make hydrocarbon fuels,” Wackett says. “CO2
is the major greenhouse gas mediating global climate change, so removing it
from the atmosphere is good for the environment. It’s also free. And we can use
the same infrastructure to process and transport this new hydrocarbon fuel that
we use for fossil fuels.”
The research is funded by
a $2.2 million grant from the U.S. Department of Energy’s Advanced Research
Projects Agency-energy (ARPA-e) program, created to stimulate American
leadership in renewable energy technology.
The U of M proposal was
one of only 37 selected from 3,700 and one of only three featured in the New
York Times when the grants were announced in October 2009. The Univ. of Minnesota’s
Initiative for Renewable Energy and the Environment (IREE) and the College of Biological Sciences also provided
funding.
Wackett is principal
investigator for the ARPA-e grant. His team of co-investigators includes
Jeffrey Gralnick, assistant professor of microbiology and Marc von Keitz, chief
technical officer of BioCee, as well as Bhan and Schmidt. They are the only
group using a photosynthetic bacterium and a hydrocarbon-producing bacterium
together to make hydrocarbons from carbon dioxide.
The U of M team is using Synechococcus, a bacterium that fixes
carbon dioxide in sunlight and converts CO2 to sugars. Next, they
feed the sugars to Shewanella, a bacterium that produces hydrocarbons. This
turns CO2, a greenhouse gas produced by combustion of fossil fuel
petroleum, into hydrocarbons.
Hydrocarbons (made from
carbon and hydrogen) are the main component of fossil fuels. It took hundreds
of millions of years of heat and compression to produce fossil fuels, which
experts expect to be largely depleted within 50 years.
