A catalyst using a single or just a few palladium atoms removed 90% of unburned methane from natural gas engine exhaust at low temperatures in a recent study. While more research needs to be done, the advance in single atom catalysis has the potential to lower exhaust emissions of methane, one of the worst greenhouse gases that traps heat at about 25 times the rate of carbon dioxide.
Reporting in the journal, Nature Catalysis, a research effort between Washington State University and SLAC National Accelerator Laboratory showed that the single-atom catalyst was able to remove methane from engine exhaust at lower temperatures, less than 350 degrees Celsius (662 degrees Fahrenheit), while maintaining reaction stability at higher temperatures.
“It’s almost a self-modulating process which miraculously overcomes the challenges that people have been fighting – low temperature inactivity and high temperature instability,” said Yong Wang, Regents Professor in WSU’s Gene and Linda Voiland School of Chemical Engineering and Bioengineering and a corresponding author on the paper.
Natural gas engines are used in about 30 million to 40 million vehicles worldwide and are popular in Europe and Asia. The gas industry also uses them to run compressors that pump natural gas to people’s homes. They are generally considered cleaner than gasoline or diesel engines, creating less carbon and particulate pollution.
Read more at Washington State University
Image: A high-performance catalyst efficiently removes unburned methane from natural gas engine exhaust by utilizing every palladium atom, while maintaining stability. The catalyst exhibits a distinctive reversible behavior, allowing palladium atoms to form highly active two- or three-atom clusters at low temperatures, which disperse back into stable single atoms at high temperatures. (Credit: Cortland Johnson from PNNL via Washington State University)