Method could scrub exhaust from cars and power plants
Fibrous protein fragments similar to those in the brains of people with Alzheimer’s disease can pull carbon dioxide out of the air.
Existing methods to capture CO2 have drawbacks. Some require toxic materials and large amounts of energy; others falter when exposed to water vapor, which fossil fuel combustion releases alongside CO2.
Because building blocks of proteins bind CO2 in blood, scientists including David Eisenberg of UCLA exposed protein fibers called amyloids to CO2 in air, mimicking conditions in a power plant chimney. Each amyloid captured one CO2 molecule, and the reaction worked even with water vapor present. The fibers released the gas when heated to 100° Celsius, allowing reuse of the amyloids. (To lower atmospheric greenhouse gas levels, CO2 would need to be stored permanently.)
The fibers do not capture enough CO2 for industrial use, but they could be improved, the authors write December 23 in the Proceedings of the National Academy of Sciences.
D. Li et al. Designed amyloid fibers as materials for selective carbon dioxide capture. Proceedings of the National Academy of Science. Published online December 23, 2013. doi: 10.1073/pnas.1231797111.
D. Castelvecchi. Turning CO2 into chalk and sand. Science News Online. August 22, 2008.