They might look more like candy, but these micro-capsules are rather more special than that. Their shiny shell allows CO2 to pass straight through—where it can be trapped by a liquid held in their core.

The little spheres are made up of a permeable polymer shell which holds a fluid with sodium carbonate in it. In areas of high CO2 concentration, the gas passes through the shell and into the liquid, where it reacts to form sodium bicarbonate—like baking soda. The capsules can then be heated to release pure CO2 in a controlled environment, where it can stored away, compressed or perhaps even reused. The capsules were described in a paper published in Nature, and it's hoped that they could be used in environments like power stations, to provide safe and affordable capture of CO2 from emitted gasses. [Nature via The Conversation]

Advertisement