The chabazite consists of a kind of ring of atoms of silicon, aluminum and oxygen, with a cesium atom in the center. The cesium atom acts like a trap door, letting carbon dioxide pass but blocking other chemicals. Webley and his team tested the chabazite in a mixture of carbon dioxide and methane -– natural gas. They also found that it worked in separating other gases such as nitrogen.
Different gases were allowed through the trapdoor at different temperatures, so it's possible to use that property to get even better selection of the carbon dioxide.
Caging Radioactive Gas
One of the more immediate applications might be getting the carbon dioxide out of natural gas deposits. Often, when drilling for natural gas, there is a lot of carbon dioxide present that has to be taken out before the natural gas can be compressed and liquefied. The chabazite could also improve the scrubbers used to take CO2 from emissions.
The work was published in the Journal of the American Chemical Society.
Photo: A naturally-occurring crystal of chabazite. Credit: Wikimedia Commons