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0 pointsWhompingWindows7y ago0 comments

Liquids have differential densities which allows them to spread into layers. If you have "compressed air" that separates into bands, you're just talking about compressing the air into a liquid phase so it can then be extracted as above. The triple point of carbon dioxide is -57 C and 5.1 atm, so in other words you'd have to get colder and higher pressure than that to even produce the liquid. Then you'd have to spin it down while it's pressurized and cooled.

Could you math it out from there and compare it to the Sabbatier reaction or to just plain old trees? I doubt you'll extract CO2 cost effectively that way.

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jf-7y ago

I’m not sure that compressing to a liquid would be necessary. https://energyeducation.ca/encyclopedia/Gas_centrifuge , which is describing the uranium enrichment process mentioned by Ichengify, states that the separation occurs while the uranium is still a gas, with the heavier fraction just being scooped out.

Also taking a quick look at the natural separation of gasses in Earth’s atmosphere, it seems that the uppermost layer consists mostly of hydrogen, helium and CO2, and that’s just under gravity.

I’m not a chemical engineer, but I’ll have a stab at what the energy for the process might be. No promises that I can reach an answer.

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0 pointsWhompingWindows7y ago0 comments

Could you math it out from there and compare it to the Sabbatier reaction or to just plain old trees? I doubt you'll extract CO2 cost effectively that way.

0 comments

jf-7y ago

Also taking a quick look at the natural separation of gasses in Earth’s atmosphere, it seems that the uppermost layer consists mostly of hydrogen, helium and CO2, and that’s just under gravity.

I’m not a chemical engineer, but I’ll have a stab at what the energy for the process might be. No promises that I can reach an answer.

j / k navigate · click thread line to collapse