MIT stated that the new system requires less energy and money to operate than other methods that require higher concentrations, such as those found in fossil emissions from fossil fuel-based power plants.
The device at the heart of the system is like a large battery that absorbs carbon dioxide from the air and passes over its electrodes as it charges. The battery then releases gas when it is discharged.
The interior of the system is described in detail by researchers – MIT postdoc Sahag Voskian and Professor T. Alan Hutton – in an article called Faradaic Electro-Swing Reactive Adsorption for CO2 Capture, published this month in the journal Energy and Environmental Science.
"In my labs, we strive to develop new technologies to deal with a variety of environmental issues that avoid the need for heat sources, changes in system pressure or the addition of chemicals to complete separation and release cycles," Hutton said before MIT News. "This carbon dioxide capture technology is a clear demonstration of the power of electrochemical approaches that require only small voltage fluctuations to drive the divisions."
As it works, the device alternates between charge and discharge. During the charge cycle, fresh air blows through the system. Carbon Dioxide Concentrates During Disposal
During the charge cycle, a reaction occurs between the piles of electrodes in the device that are coated with a special compound. The electrodes have a natural affinity for carbon dioxide and are easy to react with, even at low concentrations. When the battery is discharged, the reaction is reversed.