Surplus industrial carbon dioxide creates an opportunity to convert waste into a valuable commodity.
Surplus industrial carbon dioxide creates an opportunity to convert waste into a valuable commodity. Excess CO2 can be a feedstock for chemicals typically derived from fossil fuels, but the process is energy-intensive and expensive. University of Illinois chemical engineers have assessed the technical and economic feasibility of a new electrolysis technology that uses a cheap biofuel byproduct to reduce the energy consumption of the waste-to-value process by 53 percent.
The new findings are published in the journal Nature Energy.
Conversion of CO2 to chemicals like ethylene for plastics is possible through a process called electrochemical reduction. Typically, a stream of CO2 gas and a fluid electrolyte move through an electrolysis cell that breaks the CO2 down into molecules like ethylene on the cathode, but it also produces oxygen from water on the anode, the researchers said.
“About 90 percent of the energy required in conventional CO2 reduction is used up by the oxygen-producing, anode side of an electrolysis cell,” said Paul Kenis, a chemical and biomolecular engineering professor, department chair and study co-author. “But there is no big market for the excess oxygen, so 90 percent of the energy is essentially wasted.”
Read more at University of Illinois at Urbana-Champaign
Photo: Chemical and biomolecular engineering professor and department chair Paul Kenis, right, and graduate student Shawn Lu are co-authors of a new study that examines the feasibility of a new CO2 waste-to-value technology. Photo by L. Brian Stauffer
