Earnest Jackson Oglesby Professor
T. BRENT GUNNOE
Mechanical and Aerospace Engineering
Materials Science & Engineering
From Natural Gas to Liquid Fuels
This relationship is playing an important role in a project that U.Va. is leading—developing an inexpensive, effective method to transform natural gas into liquid fuels and high-value chemicals.
New drilling technologies have produced a glut of natural gas, which could be converted to fuels and valuable chemicals if the infrastructure were available to transport it to a central syngas facility. Because of the enormous capital investment required to build them, syngas plants only make economic sense if they process large amounts of natural gas. Unfortunately, our existing pipelines are at maximum capacity, and building new ones is extraordinarily expensive and controversial.
One solution is to develop an inexpensive technology that can be deployed locally to transform the natural gas into a liquid fuel, a fuel precursor, or a high-value chemical. “Liquids are cheap to move, and capacity can be readily added,” Gunnoe says. “With this technology, we could take surplus natural gas and produce enough fuel, for instance, to alleviate our dependence on foreign oil for transportation. Converting natural gas to liquids makes more sense than trying to replace our entire transportation infrastructure to accommodate an entirely new fuel.”
But as Davis points out, this is not easy problem to solve “There has been at least five decades of substantial effort in this arena, both from industries and universities, but I think we are tackling this problem in a new way,” says Davis. “It’s a high-risk project with high-value benefits.”
From Sunlight to Fuels
A second MAXNET Energy initiative that U.Va. researchers are participating in—the conversion of sunlight to fuels—is also designed to take advantage of the nation’s existing infrastructure. As Gunnoe points out, relying on fossil fuels to meet the worldwide demand for energy in 2050—expected to triple from current levels—would be both an environmental issue and economically and politically destabilizing. Renewable sources must fill the gap, and he believes that solar energy holds the most promise. One challenge is storing the energy produced by photovoltaic cells. “If your goal is high-energy density, you are much better off storing that energy in the chemical bonds of a liquid fuel than in a battery,” Davis says.
The researchers at MAXNET Energy envision a system in which the electricity from photovoltaic cells drives the chemical reactions needed to convert carbon dioxide and water into liquid fuels and chemicals. A key step in this chain of events is splitting water into its constituent elements, hydrogen and oxygen, a process that currently requires energy input. A key component, and, according to Gunnoe, the most challenging aspect, is the water oxidation half reaction. Materials Science and Engineering Professor Giovanni Zangari’s group utilizes titanium dioxide nanomaterials that generate the photo-induced current necessary to split water while simultaneously serving as catalysts for this process. This ensures that all protons are stripped from the water molecule to allow two oxygen atoms to form oxygen gas (O2), while protons diffuse in the solution and recombine at another electrode to form hydrogen.
A related strategy is to use a large-scale solar thermal system, such as an array of mirrors, to drive chemical processes rather than produce electricity. Mechanical and Aerospace Engineering Professor Hossein Haj-Hariri’s group is developing thermal management devices that will ensure that the heat produced is optimal for driving the chemical reaction.
Advantages That Will Resonate for Years to Come
The MAXNET Energy project creates a host of opportunities for U.Va. researchers and students that go beyond raising the visibility of the Engineering School and College. The Max Planck Institutes maintain state-of-the-art facilities, staffed by thousands of highly trained technicians. “We will be able to use equipment that would not be available otherwise,” Gunnoe says.
But as Davis points out, the major impact of the partnership will be on people. For faculty, this means extending their network of collaborators to include world-class researchers. For our postdoctoral fellows, graduate students, and, eventually, our undergraduate students, MAXNET Energy provides a superb arena for professional development. Students will be part of an international team that will meet regularly, both online and in person, sharing updates and providing feedback.
“Beyond the research discoveries we make, the ultimate measure of our success is getting our students across the ocean,” Davis says. “In addition to presenting at meetings, there will be opportunities for our students to go to Germany. They’ll have the experience of conducting research in different lab settings, developing new skillsets, and working with a range of advisors and mentors.”
This exchange also creates opportunities for Max Planck. The society foresees a shortfall of 50,000 engineers and scientists in Europe by 2030 as a result of an aging population. The partnership with U.Va. gives it a first look at new talent. Max Planck is also interested in learning how the University develops, protects, and markets its intellectual property.
Most importantly, Gunnoe and Davis believe this partnership has the potential to provide these benefits far into the future. “Our hope is that this initial five-year period will be the beginning of a longstanding collaboration that will, over time, draw in more and more researchers from U.Va.,” Gunnoe says. “This collaboration could be the first step in a major transformation for the University.”
REPRESENTATIVE PUBLICATIONS: B.N. Zope, D.D. Hibbitts, M. Neurock and R.J. Davis, “Reactivity of the Gold-Water Interface during Selective Oxidation Catalysis,” Science 330 (2010), 74-78. Pouy MJ, Milczek EM, Figg TM, Otten BM, Prince BM, Gunnoe TB, Cundari TR, Groves JT, “Flavin-catalyzed insertion of oxygen into rhenium-methyl bonds,” J. Am Chem Soc. 2012 Aug 8;134(31):12920-3 (2012).