We can keep using coal.
Australian science outfit the CSIRO is claiming a win, demonstrating a material it says offers a new approach to carbon capture: a sponge. The idea of the “sponge” – really a material called a metal-organic framework – is very straightforward. It absorbs gases at the point of release, such as capturing flue gases in a power …
If you can guarantee to capture and sensibly handle all of the products from burning coal, then what's the problem?
Of course, this is only a solution for the carbon dioxide produced. Some other issues are:
micro-particulates (i.e. soot)
sulphur oxides (which cause acid rain and respiratory problems)
nitrogen oxides and ozone (which cause photochemical smog)
mercury vapour (which is toxic)
fly ash (which is caustic and produced in large quantities)
radioactive emissions (large coal-fired power stations release more radioactivity in their flue gases, from trace elements in the coal than nuclear power stations do in their cooling water)
"and converting the C into something solid like"
and converting the C into something solid like CARBON
In any case the problem is, even in theory, it needs energy, lots and lots of it, indeed somewhat more energy than was obtained by burning the carbon in the first place.
proto-robbie; you don't got your sums right.
However, CO2 frozen gas hydrate might be stable under those conditions; this is a physical, rather than chemical reaction, and requires only water and cold to form a solid that is stable under pressure at low temperatures. The problem comes if the rpessure is reduced, or the temperature rises to the point where the hydrate breaks down.
There are some uses for CO2 that could soak up some of it, but generally these demand a pure CO2 stream, so it is useful as a step in the recovery/re-use process. The research looks nice, but I would worry about the resilience of the MOFs, especially at the elevated temperatures likely to be used in gas flue streams. (Temperatures up to 30 C reported in the paper) and likelihood of poisoning in real gases.
Why not depost it somewhere with lots of greenery... I mean plants and trees do love CO2... they get more 'food', we get more air to breathe.
That, or just find a way of using CO2 as a reliable power source. Given how much we generate, it could provide a tasty amount of juice.
"just find a way of using CO2 as a reliable power source"
Is that a joke - in which case I'll let you off otherwise please explain the magic.
Carbon burning to CO2 gives off ~400 kJ/mol or ~ 34MJ/kg - there's no other oxidation state to go to - any other chemical change NEEDS energy so it's hardly likely to be a useful power source
From Wikipedia: Precursor to chemicals
In the chemical industry, carbon dioxide is mainly consumed as an ingredient in the production of urea and methanol. Metal carbonates and bicarbonates, as well as some carboxylic acids derivatives (e.g., sodium salicylate) are prepared from CO2.
There is also some work looking to make green polycarbonate plastics from CO2, though it is early stage and unlikely to make a significant dent. The main (hopeful) future use for CO2 is to use it as a feedstock to make fuel, which is about the only chemical we need at scale to make use of the amount of CO2. This does of course take energy, but if it can be supplied from a renewable source, future CO2 release from fossil fuels would be reduced or eliminated. Methanol can be made from CO2 for example, and there is also the dry methane reforming reaction to make syngas, which can then be used to make liquid fuels via the Fischer-Tropsch process. This is arguably nicer than steam reforming, but people are unlikely to stop that, since the hydrogen it produces is much more valuable. There may be a role for small installations, but it often makes more economic sense to flare methane than transport it to market.
" This does of course take energy, but if it can be supplied from a renewable source, future CO2 release from fossil fuels would be reduced or eliminated. "
Is that really? Suppose we burn 1 ton of carbon in a power plant. As said by other, this releases about 34 MJ/kg, so in total we have almost 10MWh at the input side. Nice, however this power plant operates at 45% efficiency, so it only pumps 4,5 MWh in the grid. To reverse this reaction, and split the C off the O2, will require more energy than was produced by burning - say 12MWh. Of course, that could be provided by a renewable energy source. But if we have a renewable energy source producing 12MWh - why burn the carbon in the first place? Just use this renewable source to pump its 12MWh in the grid!
Awesome! This is the kind of science we should be spending money on, not that solar/wind bollocks that will never provide enough power to be viable, science that will provide clean-ish energy!
The only reason I can see to be spending money on "green" (synonymous with useless) energy instead of things like nuclear and technology like this is the hippys without any understanding of technology have too much lobbying power. They don't want clean and efficient energy, they want us all living a "natural" (aka hellish) existence with little to no power usage.
I think you are confusing a specific chemical with the azobenzene class. As far as I can see a particular azobenzene is bonded to this large-surface area material.
The analogy would be sodium cyanide is very toxic but the cyanide group (a nitrile actually) can be part of an organic molecule without any sig. toxic effects. In fact the breast-cancer treatment Arimidex contains 2 nitriles.
The cynic in me sees not a method of removing CO2, but a new way to generate those bloody useless Carbon credits that allow big polluters to keep on pumping out noxious fumes.
Disclaimer - I am not a greenie, but I do think we're doing a fantastic job of crapping in the only nest we've got.
" Somebody takes it...
and hopefully makes some kind of liquid fuel from it"
As mentioned previously.
Carbon burning to CO2 gives off ~400 kJ/mol or ~ 34MJ/kg - there's no other oxidation state to go to - any other chemical change NEEDS energy so it's hardly likely to be a useful power source. Maybe you'd take a hit, use energy to make a new liquid fuel, but it's now just an energy carrier like batteries or hydrogen.
And then it still ends up back in the atmosphere !
Why not send the resulting fluids somewhere where the sun always shines, such as Austrailia (lots of useless desert there) or the Sahara.
A few thounds square miles of Solar panels and you could probably generate enough energy to seperate the C from the O2.
Actually why not ship loads of water out there and generate hydrogen for fuel?
The MOF is produced using the massive energy of a beam line at the Australian Synchrotron?
That is a so-geeky place to visit (we live close by and the family loves Open Days), BUT how much energy is required in the first place to make this absorbent material?
"The MOF is produced using the massive energy of a beam line at the Australian Synchrotron?"
Er, no. The beam-line was used to analyse the structure during the development.
"the development of the materials used the powder diffraction beamline"
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