GLOBAL CHALLENGES

Washing the Air: New Devices Wash Carbon from Air We Breathe

Dave Greenfield | Date: 07-20-10 | Comments

Scientists are developing devices that remove carbon dioxide from the air. Leftover carbon dioxide can then be used in a variety of industries.

It has long been known that carbon-based fuels are emitting unhealthy amounts of carbon dioxide (CO₂) into the atmosphere. There aren�t nearly enough trees on earth to remove all this CO₂on their own. Could the answer be found in �synthetic trees?�

Researchers are developing machines designed to work in much the same way as live trees do. The idea is that they will scrub the CO₂out of the air with chemicals and reroute it for other useful purposes.

But just how do these mechanical trees work? The machines need to be compact and contain filters much like those in typical furnaces. Air is sent through the machine. Then, it hits a sorbent material that removes the carbon dioxide. Oxygen and nitrogen are then freed up and pushed away, and the extracted carbon dioxide is turned from a gas into a liquid. But what should be done with all this liquid CO₂?

Carbon dioxide filters such as these free oxygen and nitrogen from the carbon dioxide in air.

One option is that the liquid could be pumped underground and used by various industries. Food and beverage manufacturers rely on CO₂ to carbonate or deep-freeze their products. It is a source of non-toxic refrigeration. Locating these air-scrubbing machines near oil or natural gas mines and pumping the CO₂down could help the mines produce in higher quantities.

Another use would be to convert this CO₂ into useable synthetic fuel, thereby eliminating the high demand for carbon-based fuels.

A technology similar to this has been put to use to clean the air that is breathed in submarines and space shuttles. This would be a larger project and could help eliminate an enormous amount of predicted future damage to the already overtaxed ozone.