Boston: Researchers have developed a new technology to capture carbon dioxide from a stream of air — virtually at any concentration level — an advance that may pave the way for new strategies to reduce atmospheric greenhouse gas levels. The researchers from the Massachusetts Institute of Technology (MIT) in the US said that while most methods of removing carbon dioxide from a stream of gas required higher concentrations — such as those found in the flue emissions from fossil fuel-based power plants — the new method could suck out the gas even when it was present in very low concentrations.
They added that the method required significantly energy, and could even suck out the greenhouse gas at the roughly 400 parts per million currently found in the atmosphere. In a study, the researchers described the device as a large, specialised battery with a stack of electrodes that absorbs carbon dioxide from the air passing over its surface as it was being charged up, and then released the gas as it was being discharged.
The researchers said that the device alternated between charging and discharging cycles. During the charging cycle, they said that fresh air was fed into the system, and concentrated carbon dioxide was blown out during the discharging.
When the battery is discharged, the researchers said that the process ejects a stream of pure carbon dioxide, and also provides part of the power needed for the whole system.