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University of Nottingham Establishes Carbon Capture and Storage Center; One Focus To Be on Serpentinization

The University of Nottingham (UK) is establishing a Centre for Innovation in Carbon Capture and Storage (CICCS) with £1.1 million (US$2.23 million) in funding from the Engineering and Physical Sciences Research Council (EPSRC).

The center, which is due to open in October 2007, will develop novel technologies to trap and store greenhouse gases permanently and safely. One of the processes the center will work on will use “serpentinization”—the acceleration of the natural geologic process of the carbonation of a magnesium silicate material such as serpentine (Mg3Si2O5(OH)4) to magnesite (MgCO3).

The natural process can be accelerated by increasing the surface area, increasing the activity of carbon dioxide in the solution, introducing imperfections into the crystal lattice by high-energy attrition grinding, and by thermally activating the mineral by removing the chemically bound water.

The US Department of Energy Office of Fossil Fuel’s Albany Research Center has run a series of tests on similar ex-situ mineral carbonation in an aqueous system. The process developed at ARC utilizes a slurry of water mixed with a magnesium silicate mineral, olivine [forsterite end member (Mg2SiO4)], or serpentine. This slurry is reacted with supercritical carbon dioxide (CO2) to produce magnesite.

The CO2 is dissolved in water to form carbonic acid (H2CO3), which dissociates to H+ and HCO3. The H+ reacts with the mineral, liberating Mg2+ cations which react with the bicarbonate to form the solid carbonate. The process is designed to simulate the natural serpentinization reaction of ultramafic minerals.

In a review of baseline test results, the Albany researchers noted:

Tests conducted at ambient temperature (22°C) and subcritical CO2 pressures (below 73 atm) resulted in very slow conversion to the carbonate. However, when elevated temperatures and pressures are utilized, coupled with continuous stirring of the slurry and gas dispersion within the water column, significant reaction occurs within much shorter reaction times.

Extent of reaction, as measured by the stoichiometric conversion of the silicate mineral (olivine) to the carbonate, is roughly 90% within 24 hours, using distilled water, and a reaction temperature of 185°C and a partial pressure of CO2 (PCO2) of 115 atm. Recent tests using a bicarbonate solution, under identical reaction conditions, have achieved roughly 83% conversion of heat treated serpentine and 84% conversion of olivine to the carbonate in 6 hours. The results from the current studies suggest that reaction kinetics can be improved by pretreatment of the mineral, catalysis of the reaction, or some combination of the two. Future tests are intended to examine a broader pressure/temperature regime, various pretreatment options, as well as other mineral groups.

The University of Nottingham estimates that once its serpentinization process is fully developed, the mineral carbonation of CO2 will take place within minutes.

The end product magnesite can be used as aggregates for road-building or shaped into bricks for construction. Carbon dioxide makes up 40% of its weight.

Compared to other proposed processes for carbon storage, such as geosequestration, once the CO2 is locked inside the rock, it cannot revert to its previous state. Moreover, the end result is a commercial product. Fossil fuel power plants could utilize the new process by adding a reactor to their emissions treatment system, allowing CO2 to be turned into a useful building material. The Centre’s ultimate goal will be to sign collaborative agreements with power and construction companies to move forward with commercialization of the technology.




Of course ultramafics being so ancient (Archaean) and unwieldy one might see this as a probable cause for surrection. There are very rare occasions of supercritical CO2 without extreme serpentine sensitivity making this entire enterprise questionable.

Then there is the question of slurry framing which is the source of intense investigation around the world. Several key slurry chemistries have been identified and will be tracked to their logical arrest or containment. It may simply be more straight forward to grow algae with excess CO2 gases letting them freely circulate to grow new sources of nutrient and biofuels.

Volcanic ultramafic rocks are rare outside of the Archaean and are essentially restricted to the Neoproterozoic or earlier, although some boninite lavas currently erupted within back-arc basins (Manus Trough, Philippines) verge on being ultramafic.

Roger Arnold

Don't ask me; I have no idea what 'qr' is talking about either. What on earth does the age of ultramafic rocks have to do with the price of tea in China?

Serpentinization is unquestionably a very secure way to sequester CO2. But there is an obvious issue with this approach--beyond just the potential cost of the whole thing. That's the small matter of scale. Making bricks for construction is cool, but the total world market for bricks isn't large enough to sequester more than a tiny fraction of the CO2 that we emit each year.



You are right to ask. The age of intrusive ultramafic rock might predate the Archaean to the Hadean, around 4000 Ma. In either case, good quality Longjiing tea trades for around 300 yuan in Beijing and the two have little in common.

A major concern is how to contain the non-anthropogenic
CO2 generated by the 1500 active and potentially active volcanoes on earth. Just one produces ten times the amount of human made CO2. Suggestions?

Roger Arnold

Uhmm, that's very counter to data I've seen. The direct anthropogenic contribution to atmospheric carbon is ~6 GtC / yr. (GtC = gigatons carbon.) The average contribution from all volcanoes worldwide is about 1% as much.

During episodes of intense vulcanism, like that which formed the Deccan traps, the rate at volcanic CO2 may have approached the current rate of anthropogenic CO2 emissions.

Rafael Seidl

I may be wrong, but I thing qr is saying that the type of rocks suitable for this type of CO2 sequestration are only found deep beneath the surface. Also, there are a few places in nature where supercritical CO2 and such rocks coexist without forming serpentine, suggesting it may not be as safe a method of sequestration as the authors suggest. Creating a slurry would require either mining the rocks - expensive and energy-consuming - or pre-treating them in situ - idem.

Algae might be one way to transition from the exploitation of fossil fuels to a real-time carbon fuel cycle, especially if the vast surface of the tropical oceans can be leveraged.

Another option would be to use modest amounts of (PV-generated) electricity to grow giant artificial limestone islands on the open ocean, with embedded bouyancy elements and engines to move them about.

This would sequester CO2 already dissolved in the oceans, reducing outgassing due to rising ocean temperatures. This in turn would at least reduce the rate at which atmospheric CO2 concentrations are rising. The islands would pay for themselves as fish nurseries, vacation spots or permanent habitable landmass. You could also grow algae on their surface / inside an artificial limestone perimeter and produce biofuel from that.

The key concept here is that it is not necessary to sequester CO2 at source.


I recently went on a geology field trip where one of the sites was magnesite formed in serpentine. Also pumpellyite just so rockhounds know I'm genuine. These utramafic rocks started deep below ocean trenches but are now at the surface eons later.

Which means my feet are firmly on the ground. This proposal is pure fantasy and cannot possibly work. The energy required to scrub, compress and pump CO2 to below suitable ocean trenches will far exceed the energy gained. Still it's an entertaining project for the scientists who got the grant.

Hopefully we will soon realise the only surefire remedy for CO2 emissions is not to create them in the first place.

Bud Johns

I cannot understand why no one seems to mention the destruction of the tropical rain forests. Automatic CO2 absorbtion, while oxygen is produced! I say we push to not only stop thier destruction, but try to restore what has been lost! Raf, whatcha think??


Bud, good idea. Are you willing to pay to preserve the forests?

Don't forget that the U.S. and the E.U. have deforested all their forests ages ago.

If you want to prevent people in developing countries from doing the same, then consumers in the West will have to pay up.

This is called 'avoided deforestation' or 'compensated reduction'. (A Google search with these terms will show you more about these proposals.)

The problem is that most of us talk about rainforest preservation, but when it comes to paying for it, we back off. So that's a bit hypocritical.

richard schumacher

Just to make the annual six gigatons of human-contributed carbon more vivid, that is equivalent to ten thousand cubic kilometers of CO2 at atmospheric pressure and temperature. And that's just for the year 2005. Let that sink in for a few moments, and then try to imagine capturing, transporting, and sequestering that much material.

That is roughly 25 ppm of the entire Earth's atmosphere. However the measured annual increase in CO2 content is about 1.5 ppm, implying that about 94% of our CO2 contribution is getting naturally sequestered. This leaves a mere six hundred cubic kilometers per year for us to deal with. Managing even that fraction is physically impossible, never mind economically feasible. Our only option is to not create that much fossil-derived CO2 in the first place.

Wind, hydro, and ground-based Solar power are all very nice but they won't make a rat's ass of difference in a world in which nine billion people all want to enjoy a Western European standard of living. Vastly increased use of nuclear power had better be in our immediate future or all of our grandkids will suffer.

Rafael Seidl

@ Bud Johns -

reducing rainfoest destruction ought to be the #1 priority wrt CO2 mitigation, but it's politically very hard to get Brazil, Indonesia et. al. to stop cutting down their forests. It's not just a question of the price tag you put on preservation, it's that the land gets cleared to grow e.g. soy beans that are exported to Europe and other rich nations as cattle feed. The highly subsidized surplus of meat is then dumped in the third world. Gotta love the Frenchies.



Regarding deforestation you might find this 2003 NASA/DOE study published in Science interesting.

"Our study proposes climatic changes as the leading cause for the increases in plant growth over the last two decades, with lesser contribution from carbon dioxide fertilization and forest re-growth," said Ramakrishna Nemani, the study's lead author from the University of Montana, Missoula, Mont.


Of course the debate presupposes CO2 causative of temperature. At 0.0378 (NCAR 2005)percent of our atmosphere this appears a bit optimistic in light of orbital mechanics and solar activity.

Raphael, man made limestone islands! Motor driven! And I was excited about a new Tesla... Fantastic!

@Rafael Seidl

//but it's politically very hard to get Brazil, Indonesia et. al. to stop cutting down their forests. It's not just a question of the price tag you put on preservation, it's that the land gets cleared to grow e.g. soy beans that are exported to Europe and other rich nations as cattle feed.//

Well, Brazil, Indonesia, Papua and a coalition of 20 tropical forest countries have precisely launched the 'avoided deforestation'/'compensated reduction' concepts to deal with this because the schemes can break the deforestation pace by putting a price on the carbon sink. The IPCC likes the idea.

But the question remains: is the West willing to pay up? I'm afraid not. And so long as it isn't, this is mainly a problem sustained by the West.

We don't have to politically convince Brazil and Indonesia because they proposed the concept; we have to convince the West.

Paul Dietz

However the measured annual increase in CO2 content is about 1.5 ppm, implying that about 94% of our CO2 contribution is getting naturally sequestered.

You dropped a decimal point. About half our annual CO2 emissions are staying in the atmosphere; most of the rest is thought to be dissolving into the oceans.

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