Naked Science Forum
Non Life Sciences => Chemistry => Topic started by: Graham_Potter on 23/10/2008 11:24:49
-
Graham_Potter asked the Naked Scientists:
In a recent programme (http://www.thenakedscientists.com/HTML/podcasts/show/2008.08.03/), they talked of storing carbon dioxide under ground as there is too much about.
As carbon dioxide is CO2, is there no way we have of splitting it into its components carbon and oxygen in the same way that passing an electric current through water (H2O) produces hydrogen and oxygen? Is there no CO2 converter or have plants cracked something humans can't?
Graham Potter
Cambridge
England
What do you think?
-
What would be the point?
A lot of energy would be required to 'decompose' the CO2. This would negate the energy which was obtained from burning the original Carbon. You'd need to get that energy from somewhere else.
It's a downhill process, I'm afraid. The same applies to splitting water to get hydrogen and oxygen. There's no such thing as a free lunch.
Of course plants have 'cracked it'. They use the energy in sunlight to produce their food - which is what we eat and the plants use. We'd not be here if it weren't for the plants.
-
Incidemtally, the simple answer is no. Liquid CO2 doesn't conduct and CO2 in solution in water acts as a weak acid- the products at the electrodes are H2 and O2.
You might be able to do this in some strange solvent, but I doubt it.
The only reason I can think of to do this would be if (big if) we were able to get a massive source of cheap energy and use it to strip CO2 from the air to reduce the greenhouse effect.
-
How about at high temperatures, sY, with very high voltages applied directly to the CO2?
-
Very high voltages are not a feature of electrolysis.
-
Oh. Fair enough. I suppose you need to form ions for it to happen.
-
Ok people thanks for your attempts to answer the question but you all seem hung up on electrolysis, The question was not about changing CO2 to its elements by electricity but by any means known to man, If you missed the programme the speaker was referring to storing CO2 underground deep underground and at that depth it would stay in liquid form due to depth and pressure, that’s what he said, This was to reduce the amount of CO2 in the atmosphere and hence reduce the green house effect. So I thought why store it can’t we convert it. Oxygen which is what seems to be lacking in this world
-
Ok people thanks for your attempts to answer the question but you all seem hung up on electrolysis,
That may have been something to do with the title of the thread.
We don't have a shortage of oxygen, we have a shortage of (easily used, nicely packaged) energy.
-
Ok people thanks for your attempts to answer the question but you all seem hung up on electrolysis, The question was not about changing CO2 to its elements by electricity but by any means known to man, If you missed the programme the speaker was referring to storing CO2 underground deep underground and at that depth it would stay in liquid form due to depth and pressure, that’s what he said, This was to reduce the amount of CO2 in the atmosphere and hence reduce the green house effect. So I thought why store it can’t we convert it. Oxygen which is what seems to be lacking in this world
Yes you can.To link this thread to another on here, burning magnesium in a CO2 atmosphere will seperate the carbon and oxygen as the magnesium is more reactive than the carbon. Of course the you're left with Ganesium oxide not free oxygen.