Here is one of those questions that exposes that absolute ignorance of the person asking it, but anyway, is it straightforward (or even possible) to separate pure elemental carbon from carbon dioxide by stripping off the oxygen atoms from the CO2 molecule?
Isn’t that what an underwater rebreather apparatus does? Scrub the CO2 and release O2? Maybe it’s not that simple…
No; a rebreather just absorbs the CO[sub]2[/sub]; in the case of diving apparatus, fresh oxygen is added from a compressed tank.
CO[sub]2[/sub] is where plants get most (all?) of the carbon that makes up the bulk of their structure. I doubt that, during the various organic chemical reactions, it’s ever in the form pure carbon though.
Maybe you could use plants to trap the CO[sub]2[/sub] then burn them for coke, which I belive is a form of pure carbon. That’s probably far from the most efficent method, but it at least shows it’s possible.
It can be done, but takes as much energy as is released in burning the carbon, about 2,560 kcal per pound. The laws of thermodynamics ensure us that there’s no clever way of getting around that energy requirement.
There are easier ways of getting raw carbon. The extremely slow burning process that makes charcoal yields decent carbon.
If it’s the oxygen you’re really after, use plants. Photosynthesis rocks!
Your use of the term “separate” implies that you are starting with a mixture containing elemental carbon and CO2. If this is the case the separation is very simple since, at normal temperature and pressure, carbon is a solid (graphite, diamond, or other amorphous forms) and CO2 is a gas.
If your question is how do you convert CO2 to carbon or vice versa then that is an entirely different issue which has been addressed in earlier posts.
Which are trying to answer?
Here’s a post on broadly the same subject:
I started with the simplistic assumption that you had a bunch of C02, say in gas form, and that you wanted to split it into its components, such that you would end up with a pile of carbon here, and a pile of oxygen there. The mental model I had was of water, which is split into oxygen and hydrogen by running a current through it. To judge by the thread **Lumpy ** cited, it’s not so straightforward as that for CO2, so I guess my question is why? And by way of context, let me say my knowledge of chemistry is pretty near nil.
Get some dry ice. (That’s frozed carbon dioxide if you weren’t aware.) Get some magnesium. Dig a hole into the dry ice. Put the magnesium in the dry ice. Burn the magnesium. You will get carbon and magnesium oxide.