Cheap Plastic Sand/Composite Absorbs CO2 Like Crazy

Summary

January 5, 2012:

A diary on the blogsite DailyKos reports on a paper from the Journal of the American Chemical Society on a UCLA experiment on a material capable of adsorbing Carbon Dioxide from the atmosphere¹.

The material, polyethylenimine, or PEI, has long been known to adsorb CO2 from the air, but it's brittle nature made it impractical to use. The UCLA scientists tried using fumed silica, a material made from ordinary sand, as a base for the PEI. The silica is strong and its highly-branched surface gives it a large surface area for its weight. In lab tests, the PEI-coated silica adsorbed a remarkable amount of CO2 from the air in the test chamber.

This material might possibly be used in carbon-scrubbers to reduce CO2 from air pollution. The PEI/silica composite can be reused by heating the material to 85 degrees C.

The material is not a complete solution to the problem of carbon emissions, because the captured CO2 still needs to be stored in some way. The Kos writer suggests that using captured CO2 and electricity from sources like wind and solar to make methane could be a renewable — if expensive — alternative to natural gas.

The other, obvious application for a stong CO₂ binding substance is in atmosphere recovery - for example in rebreathers, submarines, space ships and other sealed systems.

Source

Bibliography

1. Original paper: Carbon Dioxide Capture from the Air Using a Polyamine Based Regenerable Solid Adsorbent

2. DailyKos: Cheap plastic/sand composite absorbs CO2 like crazy

Game and Story Use

• Carbon scrubbers utilizing this PEI/silica composite might be a common pollution control feature in a setting Twenty minutes into the future
• The formula for the material and/or a process to make it practical for industrial use might make a good MacGuffin
• There is a limit to how much CO2 the PEI composite can adsorb before it gets saturated; but in a Mad Science plot, perhaps someone has developed a polymer that adsorbs CO2 —- and won't stop!!! The players have to stop this insidious menace before a lack of CO2 kills off all plant life on earth!!!
• You can impress your players by explaining to them the difference between "absorbtion" and "adsorbtion".
  • Okay, so they won't be all that impressed.

Footnotes

1. Although the Kos piece uses the word "absorbs" in its title, the author states in the text that the technical term is "adsorbs", because the CO2 sticks to the surface of the material rather than being soaked up by it, as water is in a sponge