An alternative CO2 capture process

SCIENTISTS at the Department of Energy’s Oak Ridge National Laboratory (ORNL), US have developed a simple, alternative process that could be used to remove CO2 from coal-burning power plant emissions. The process requires 24% less energy than industrial benchmark techniques. Last October UN climate scientists warned that rapid and unprecedented changes are needed in order to limit global temperature rise to 1.5°C above pre-industrial levels. The capture and storage of CO2 released from fossil fuel emissions could help to limit this increase, but it requires the development and large-scale deployment of energy-efficient carbon capture technologies. The team at ORNL developed a CO2 scrubber after “rediscovering” a class of organic compounds called bis-iminoguanidines (BIGs). BIGs were recently noted for their ability to selectively bind anions, and the researchers realised the ability of BIGs to bind and separate anions could be applied to bicarbonate anions. This led them to develop a CO2-separation cycle which uses an aqueous BIG solution.