Sustainability: Just Around the Bend
by Jeffrey Martin '04, '05 (M.A.)
It’s a well-known fact that carbon dioxide (CO2) is one of the greater threats to the world’s climate. Slowing the release of greenhouse gases has been a central focus in the battle against climate change. But what if CO2 could actively be removed from the air? And what if it could be used to make something?
Peter Graham, Ph.D., associate professor of chemistry, has spent the last seven years researching CO2 activation, working to destabilize the CO2 molecule and use it as a chemical building block —to create things.
“We are doing chemistry in the laboratory inspired by the way plants use photosynthesis to break down CO2 into all the carbon materials that make up the plant,” Graham explains. ”We can’t replicate that process directly, but we can use it to learn new ways to break apart and use CO2.”
Doing this is easier said than done. “CO2 is a very stable molecule,” Graham says. “That’s why there’s too much of it in the atmosphere: It’s difficult to turn it into something else.”
In his lab, Graham introduces pure CO2 to metallic precatalysts and measures the reaction. He found that compounds containing tungsten and molybdenum have the ability to “bend” the CO2 molecule.
“In the presence of carbon dioxide, one of these transition metals can grab one of the carbon-oxygen bonds and weaken it,” Graham says. “From there, we can introduce another compound to react with the carbon and use it to build chemical materials.”
But what kind of materials could come from this kind of reaction? According to Graham, what comes to mind is, ironically, one of the worst pollutants on earth: plastics.
“It might be possible to make some plastics using CO2,” Graham says. “For example, if it could be reacted with ethylene gas, the resulting material could be used to make latex paints, disposable diapers and many other products. This would be a much more sustainable way to build carbon-based materials.”
While many hurdles between successfully destabilizing a CO2 molecule and actually manufacturing plastic remain, Graham hopes that potential environmental and economic benefits will help ease the way.
“Companies that might ultimately employ this method could harvest CO2 from smokestacks instead of allowing it to vent into the atmosphere,” he says. “In addition to this environmental benefit, they would wind up with plastic products that they can sell to consumers.”
Graham’s work has been recognized by the American Chemical Society Petroleum Research Fund, which awarded him a $65,000 grant in 2013. His research has also been a recurring presence in SJU’s Summer Scholars program since 2009. Each year, students who work with Graham present their work at the National Meeting of the American Chemical Society, and their findings have been published in the journal Organometallics.
“It may be some time before true changes occur regarding how we use carbon dioxide,” says Graham. “In the meantime, it’s important for researchers, including my students and me, to gain an understanding of how metal complexes interact with CO2 to help develop new catalysts that will make its utilization possible.”