Thread: Carbon dioxide made into rock.

Reference : New Scientist, 19 July 2014, page 30.

An interview with Dr. Juerg Matter covers the idea of converting waste CO2 into solid material for ultra long term storage. This is done by dissolving the gas in water, and then reacting it with calcium and magnesium silicates (which are incredibly common minerals) to make carbonates. This can be done by pumping the carbonated water deep underground, where the CO2 will come into contact with those minerals. This has the advantage over other CO2 storage that it is almost impossible for the CO2 to seep up through rock strata and again enter the atmosphere.

Basalt rock is perhaps the most common rock on planet Earth, and it contains the minerals needed. Carbonated water pumped into such rock strata will end up producing the carbonates needed, and this process takes no more than a year to consume all the gas.

Is this the answer to global warming?

Originally Posted by skeptic

Reference : New Scientist, 19 July 2014, page 30.

An interview with Dr. Juerg Matter covers the idea of converting waste CO2 into solid material for ultra long term storage. This is done by dissolving the gas in water, and then reacting it with calcium and magnesium silicates (which are incredibly common minerals) to make carbonates. This can be done by pumping the carbonated water deep underground, where the CO2 will come into contact with those minerals. This has the advantage over other CO2 storage that it is almost impossible for the CO2 to seep up through rock strata and again enter the atmosphere.

Basalt rock is perhaps the most common rock on planet Earth, and it contains the minerals needed. Carbonated water pumped into such rock strata will end up producing the carbonates needed, and this process takes no more than a year to consume all the gas.

Is this the answer to global warming?

Sounds interesting, but I'd like to see what the reaction scheme looks like. I don't have the New Scientist issue you refer to. Was a reaction scheme included and can you reprint it here? What slightly bothers me is that silicates can be seen as salts of silicic acid, which is a weaker acid than carbonic acid, so I can't immediately see how these reactions would work.

http://en.m.wikipedia.org/wiki/Carbo...silicate_cycle

Exchemist
I do not have those details, but I do know that the reaction occurs. It is, in fact, a natural sequestration mechanism which removes CO2 from the atmosphere on a steady basis (though too slow for our current crisis) at all times. Carbonates are the result. This process is reversed via vulcanism, wich spews the released CO2 back into the atmosphere.

The reference above gives a few details.

Originally Posted by skeptic

Carbonate

Exchemist
I do not have those details, but I do know that the reaction occurs. It is, in fact, a natural sequestration mechanism which removes CO2 from the atmosphere on a steady basis (though too slow for our current crisis) at all times. Carbonates are the result. This process is reversed via vulcanism, wich spews the released CO2 back into the atmosphere.

The reference above gives a few details.

Aha, thanks very much: CaSiO₃ + CO₂ <-> CaCO₃ + SiO₂, the silicate in question being an inosilicate. So Carbonates and quartz are the products of the reaction.

I found this silicate/carbonate cycle very interesting, especially the reverse reaction taking place during subduction of the lithosphere and the explanation for the absorption of the pimordial carbon dioxide atmosphere.

But indeed, if the rate of reaction is fast enough, it sounds attractive as a way of absorbing CO2 safely into the sold state.

Tagging on to this thread as it does sound very tendentious,isn't carbon dioxide used to put out fires?

Since large scale forest fires are a side effect of global warming and carbon dioxide is being envisaged as being captured in industrial quantities in carbon capture and storage is there no way very large amounts of carbon dioxide can be used to combat forest fires?

Could it be injected into the water they dredge up out of the seas and lakes with planes?

Originally Posted by geordief

Tagging on to this thread as it does sound very tendentious,isn't carbon dioxide used to put out fires?

Since large scale forest fires are a side effect of global warming and carbon dioxide is being envisaged as being captured in industrial quantities in carbon capture and storage is there no way very large amounts of carbon dioxide can be used to combat forest fires?

Could it be injected into the water they dredge up out of the seas and lakes with planes?

I doubt this would work. CO2 works by displacing the oxygen from the fire, long enough for it to cool down enough not to reignite when the CO2 cloud disperses. In a large volume forest fire, in the open, this does not seem feasible to me. My understanding is CO2 is used on small fires with low "thermal mass", such as electrical fires. I suspect it only works for these.

As for dissolving it in water, I think the amount dissolved would be tiny compared to what would be required.

thanks. I was embarassed to ask but that is not unusual....

Originally Posted by geordief

thanks. I was embarassed to ask but that is not unusual....

You should never be embarrassed to ask. Anyone who makes you embarrassed deserves to ostracised. We are all ignorant of far more than we have knowledge of.

Would it not be easier to feed cyanobacteria blooms, since that is their life's work?

Originally Posted by skeptic

Reference : New Scientist, 19 July 2014, page 30.

An interview with Dr. Juerg Matter covers the idea of converting waste CO2 into solid material for ultra long term storage. This is done by dissolving the gas in water, and then reacting it with calcium and magnesium silicates (which are incredibly common minerals) to make carbonates. This can be done by pumping the carbonated water deep underground, where the CO2 will come into contact with those minerals. This has the advantage over other CO2 storage that it is almost impossible for the CO2 to seep up through rock strata and again enter the atmosphere.

Basalt rock is perhaps the most common rock on planet Earth, and it contains the minerals needed. Carbonated water pumped into such rock strata will end up producing the carbonates needed, and this process takes no more than a year to consume all the gas.

Is this the answer to global warming?

I'm guessing they use high press and some sort of heterogeneous catalyst convertor, rhodium or platinum. Though they might not need to since the temperatures at that level probably do provide for sufficient magnitude of particular collisions.


Interesting stuff!