Carbon capture technology is a hot topic right now. Tech developers take different approaches to what happens with the carbon dioxide after it is captured. Some projects under development in the Midwest are working on ways to convert the captured CO2 to useful products such as ethanol.
The U.S. Department of Energy recently announced it will provide $2 million in funding over three years for a CO2-to-ethanol project led by Northern Illinois University and Argonne National Laboratory. Plus the National Science Foundation recently granted researchers at the Missouri University of Science and Technology a $500,000 grant for similar work.
The NIU research team first captures the CO2 directly from the air. The goal is to intercept it before it is emitted into the atmosphere and then convert it to fuel. This would lower manufacturing emissions and help industrial facilities achieve carbon-neutral or carbon-negative status.
They developed a novel catalyst that can break down CO2 and water molecules and reassemble them into useful products such as ethanol. The catalyst uses electricity as a power source and performs the reaction with a high level of efficiency but at a low cost. The process can be even greener by incorporating renewable energy.
“This is an integrated system that can capture carbon dioxide and convert it to chemicals using electricity that is supplied from renewable power sources such as solar and wind,” Tao Xu, a chemistry professor at Northern Illinois University, told Centered. “It doesn’t have any carbon footprint. Rather, it decreases the carbon.”
Similarly, the Missouri S&T research team is designing a catalyst to speed up the process of using captured CO2 to create carbon-rich products by using lower electricity voltages and pressures than other methods.
As with all research and development, the NIU team has encountered challenges. A main one is that capturing carbon from the open air requires concentrating the CO2 from the emissions source to work properly in the conversion process. But industrial facilities emit more greenhouse gases than just CO2, so those must be separated. Other challenges are maximizing the conversion process efficiency and ensuring the purity of the final ethanol product.
The NIU team will spend the next three years perfecting a low-cost prototype to cleanly convert CO2 and water to ethanol. After that, Xu intends to try collaborating with industry to further scale the technology and adapt it to different industrial settings.
“In different industrial manufacturing, they have very different processes,” Xu said. “To find out the correct adaptation between our system and their emissions facilities, we have to dig into that and make this technology viable to a wide range of industries.”
The integrated capture and conversion system could benefit other heavy CO2 generating industries such as making steel or concrete.
“We are very optimistic that the successful delivery of this technology could attract a wide range of industries,” Xu said. “I hope our technology eventually can contribute to the circular economy and make our environment more sustainable for the next generation.”