Carbon Dioxide 'Sponge' Takes Step Towards Cleaner Energy

A newly developed sponge-like plastic that is capable of soaking up the notorious greenhouse gas carbon dioxide (CO2) could ease our transition away from harmful fossil fuels and toward cleaner energy, according to a new study.

The material - similar to the plastics used in food containers - could play a role in President Obama's plan to cut CO2 emissions 30 percent by 2030, and could also be integrated into power plant smokestacks in the future, researchers say.

"The key point is that this polymer is stable, it's cheap, and it adsorbs CO2 extremely well. It's geared toward function in a real-world environment," researcher Andrew Cooper, Ph.D, said in a statement. "In a future landscape where fuel-cell technology is used, this adsorbent could work toward zero-emission technology."

CO2 adsorbents are most commonly used to remove the greenhouse gas pollutant from smokestacks at power plants where fossil fuels like coal or gas are burned. But Cooper and his team intend to do more than that; they hope this organic polymer can lead to reduced pollution entirely.

The new material would be part of an emerging technology called an integrated gasification combined cycle (IGCC), which can convert fossil fuels into hydrogen gas. But the IGCC process yields a mixture of hydrogen and CO2 gas, which must be separated. This adsorbent, just like a kitchen sponge swells when it takes up water, balloons when it soaks up CO2 in the tiny spaces between its molecules. When the pressure drops, Cooper explains, the plastic deflates and releases the gas, which they can then collect for storage or convert into useful carbon compounds.

Using these types of polymers also have many advantages, besides the promise of cleaner energy and reduced pollution. The material can withstand harsh conditions, such as being boiled in acid, adsorb CO2 without also taking on water vapor - which can clog up other materials and make them less effective - and is inexpensive.

"And in principle, they're highly reusable and have long lifetimes because they're very robust," Cooper added.

The report on the material will be presented at the 248th National Meeting & Exposition of the American Chemical Society (ACS), which ends Thursday.