Researchers at MIT have developed a new way of removing carbon dioxide from a stream of air that could be a powerful tool in the battle against climate change.  The new system can pull carbon dioxide out of almost any concentration level of the gas, even including the roughly 400 parts per million level currently found in the atmosphere.

The technique is described in a new paper in the journal Energy and

Environmental Science and is based on passing air through a stack of

electrochemical plates. The device is essentially a large battery that absorbs

carbon dioxide from the air passing over its electrodes as it is being charged

up, and then releases the gas as it is being discharged.

To use it, the device would simply alternate between charging and

discharging.  Fresh air or some other

feed gas would be blown through the system during the charging cycle and then

pure, concentrated carbon dioxide would be blown out during discharging.

The specialized battery uses electrodes coated with a compound called

polyanthraquinone, which is composited with carbon nanotubes.  These unique electrodes have a binary

affinity to carbon dioxide, which means that they either strongly want to

capture carbon dioxide or not at all, depending upon whether the device is

charging or discharging.

Carbon dioxide is important in many industries such as soft drinks and greenhouse agriculture.  With this device, the stuff could literally be pulled out of the air.  And, of course, in power plants where exhaust gas is dumped into the air, these novel electrochemical cells could be used to prevent the emission of CO2 into the atmosphere.  At the right price, this could be a game changer.

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MIT engineers develop a new way to remove carbon dioxide from air

Photo, posted August 9, 2007, courtesy of William Clifford via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.