Carbon dioxide, or CO2, is a greenhouse gas that causes pollution all around the world. Removing pollution from the air is a key area of research around the world. Engineers from MIT have announced that they have developed a new way of removing carbon dioxide from a stream of air that could be a new way to fight pollution of this sort.
MIT says that the system can work on virtually any concentration level, even as low as the 400 parts per million that is currently found in the atmosphere. The team notes that most methods of removing carbon dioxide require higher concentrations along the lines of concentrations found at fossil fuel-burning power plants.
The team notes that their new method is less energy-intensive and less expensive than other methods. The process is based on passing air through a stack of charged electrochemical plates. The device is a large, specialized battery that absorbs carbon dioxide from the air or other gas stream passing over its electrodes as it is being charged up.
As it is being discharged, it releases the gas. In operation, the device would alternate between charging and discharging with fresh air or feed gas blowing through the system during the charging cycle and pure, concentrated carbon dioxide blown out in discharge. The surface of the electrodes are coated with a compound called polyanthraquinone composited with carbon nanotubes.
When the device is discharged, it can provide part of the power needed for the whole system to operate and ejects a stream of pure carbon. The system operates at room temperature and normal air pressure. The team says that the carbon dioxide ejected from the machine could be used by greenhouses or carbonated drink bottling plants. It could also be injected underground for long term storage.