Cornell scientists convert carbon dioxide, create electricity
ITHACA, N.Y. – While the human race will always leave its carbon footprint on the Earth, it must continue to find ways to lessen the impact of its fossil fuel consumption.
“Carbon capture” technologies – chemically trapping carbon dioxide before it is released into the atmosphere – is one approach. In a recent study, Cornell University researchers disclose a novel method for capturing the greenhouse gas and converting it to a useful product – while producing electrical energy.
Lynden Archer, the James A. Friend Family Distinguished Professor of Engineering, and doctoral student Wajdi Al Sadat have developed an oxygen-assisted aluminum/carbon dioxide power cell that uses electrochemical reactions to both sequester the carbon dioxide and produce electricity.
Their paper, “The O2-assisted Al/CO2 electrochemical cell: A system for CO2 capture/conversion and electric power generation,” was published July 20 in Science Advances.
The group’s proposed cell would use aluminum as the anode and mixed streams of carbon dioxide and oxygen as the active ingredients of the cathode. The electrochemical reactions between the anode and the cathode would sequester the carbon dioxide into carbon-rich compounds while also producing electricity and a valuable oxalate as a byproduct.
In most current carbon-capture models, the carbon is captured in fluids or solids, which are then heated or depressurized to release the carbon dioxide. The concentrated gas must then be compressed and transported to industries able to reuse it, or sequestered underground. The findings in the study represent a possible paradigm shift, Archer said.
“The fact that we’ve designed a carbon capture technology that also generates electricity is, in and of itself, important,” he said. “One of the roadblocks to adopting current carbon dioxide capture technology in electric power plants is that the regeneration of the fluids used for capturing carbon dioxide utilize as much as 25 percent of the energy output of the plant. This seriously limits commercial viability of such technology. Additionally, the captured carbon dioxide must be transported to sites where it can be sequestered or reused, which requires new infrastructure.”
The group reported that their electrochemical cell generated 13 ampere hours per gram of porous carbon (as the cathode) at a discharge potential of around 1.4 volts. The energy produced by the cell is comparable to that produced by the highest energy-density battery systems.
Another key aspect of their findings, Archer says, is in the generation of superoxide intermediates, which are formed when the dioxide is reduced at the cathode. The superoxide reacts with the normally inert carbon dioxide, forming a carbon-carbon oxalate that is widely used in many industries, including pharmaceutical, fiber and metal smelting.
“A process able to convert carbon dioxide into a more reactive molecule such as an oxalate that contains two carbons opens up a cascade of reaction processes that can be used to synthesize a variety of products,” Archer said, noting that the configuration of the electrochemical cell will be dependent on the product one chooses to make from the oxalate.
Al Sadat, who worked on onboard carbon capture vehicles at Saudi Aramco, said this technology in not limited to power-plant applications. “It fits really well with onboard capture in vehicles,” he said, “especially if you think of an internal combustion engine and an auxiliary system that relies on electrical power.”
He said aluminum is the perfect anode for this cell, as it is plentiful, safer than other high-energy density metals and lower in cost than other potential materials (lithium, sodium) while having comparable energy density to lithium. He added that many aluminum plants are already incorporating some sort of power-generation facility into their operations, so this technology could assist in both power generation and reducing carbon emissions.
A current drawback of this technology is that the electrolyte – the liquid connecting the anode to the cathode – is extremely sensitive to water. Ongoing work is addressing the performance of electrochemical systems and the use of electrolytes that are less water-sensitive.
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This article is a joke, right?
This process is eerily similar to the whole energy from water through Hydrogen concept that keeps raising its ugly head amongst those unfamiliar with the laws of thermodynamics. For heavens sake, H2O and CO2 are products of combustion and it is not possible under any conditions to use them as a fuel and generate energy without dumping in much more energy somewhere else. Stop looking for ways to violate the laws of thermodynamics already and work on doing something possible and potentially useful!
Yeah, they Carnot work.
I agree but the purpose of the process is to concentrate the CO2 from 5% to reduce the volume of gas to be handled/stored.
This is great news, now we don’t need those awful trees!
as long as we have enough nuclear energy to smelt the aluminium, I guess we can carry on burning fossil fuel…..
Is the aluminum consumed during the reaction?
If not, where is the energy necessary to break the carbon oxygen bond coming from?
…Yes….
urederra
August 5, 2016 at 6:49 am
2·Al(0) + 6·CO2 —–> Al2(C2O4)3 (aluminum oxalate)
So, CO2 is reduced but Aluminum is oxidized and, as many people said already, is consumed in the process.
Thanks for that urederra…
I’m sure that Anthony tosses articles like this at us knowingly (of course!) – just to entertain us on a slow Friday.
Thanks AW! 🙂
It’s from Cornell, so keep the red caution flags out for an extended period and push for further research to check it by a different group, and one that audits cost feasibility in the process.
This is an excellent way of both getting rid of excess financial resources and a pesky plant food at the same time. Win-win!
Best comment yet ! Many stars ……
It wins the Carl Sagan Award too.
I have hard time believing this could possibly generate more electricity than what’s needed to create the Aluminium used in the reaction.
‘Kasuha’ is Hausa word (lingua franca of West Africa and derived from Arabic) for marketplace. “Na tafi kasuha.” – I’m going to the marketplace. A Nigerian connection?
> A Nigerian connection?
No
Thermodynamically, this is an energy CONSUMER, not a producer.
The net reaction for converting carbon dioxide to oxalate is (in acidic conditions):
2e- + 2H+ + 2 CO2 -> H2C2O4 (-0.386 V)
The ultimate source of the electrons is the metal on the far left of the diagram. This gets consumed and converted into metal ions in the electrolyte.
The energy required to produce the metal (unless one is using an active ‘native metal’ such as iron from the earth’s core) will exceed the energy produced by the cell itself. A metal at least as active as iron
Fe++ + 2 e- ® Fe (-0.44 V)
will be necessary. The nitrogen is irrelevant. The oxygen will also gather electrons, stealing some of the energy provided by the raw metal.
..In the original paper it also mentions requiring 100% Oxygen…?
An energy consumer compared to separation, compression, transmission and sequestration? I don’t think so, but they didn’t make that argument and that’s the only comparison that might make the energy look even marginally favorable. They allude to Life Cycle Analysis, but that one looks selective.
Until someone refutes the work they did, I believe that in an AlCl3 molten salt with a feed that is 80/20 CO2/O2 they get what they said. I suspect that their electrical production might be less favorable in scale up and even less in the “real” world. This is ought to be worth several grants and a few more post graduate degrees. We ought to check back in 2020 or 2025 and see how it’s coming along.
Overall, the article is simply saying, “it looks like a possible possibility, so please send money so we can continue to investigate the possibility.”
Aluminum production (not counting mining and transportation) 30yrs ago was around 7 -8 kWh/lb. The mining, processing and transportation was ~ about the same amount (added on), since 4 tons of bauxite were required to make one ton of aluminum and the processing of the bauxite yielded 2 tons of Al2O3 to be fed into the electric smelters.
Look, at a glance, to scale this thing up to where it efficiently can process a significant amount of CO2 coming from a coal-fired electricity plant, I’ve little doubt that it would dwarf the thermal plant. Also, it is sensitive to water in the stream. The set up to clean and prepare the gas for this process would also likely be more than half the size of the thermal plant.
The aluminum probably has a low efficiency in cheap configurations. I would require creating an anode with nano scale aluminum having multi acres of area exposed to the electrolyte (perhaps having a risk of explosion). Finally, a liquid electrolyte of giant proportions would be likely impractical on cost, handling and safety. They should be looking at solid electrolite materials.
So much pie in the sky and no ice cream.
Clearly they “want to believe”. What a great fisking of a stupid idea by the commenters here. Combine ignorance of the second law with ignorance of the manufacture costs of aluminum with wishful thinking–you get garbage.
Yup.
Ah, wonderful, PHD Research grade B.S. If we could only capture the energy (wasted) on such products, we could LIGHT L.A. (Lah-Lah) land and New Stupid City with this power. Coming soon (like HOT FUSION) to a fantasy near you. Only people in Lah Lah land and STUPID cities need apply.
Wow, a perpetual motion machine that purports to reduce life-giving CO2. Let’s get right on this.
I think reading the article would clear up some questions for the expert chemistry scholars responding and should create a few more. Trying to get past the apparently obligatory save the planet by removing CO2, the chemistry seems to work in the laboratory. Is it energy efficient? Depends on comparison. If it is compared to sequestration, it might look really good. They didn’t do that. I have some qualms with AlCl3 (anhydrous) being particularly practical, useful or economical in any real application. Also, they claim aluminum oxalate is a valuable product. In what quantity? And are we collecting it from my car? Power from 80/20 (CO2/O2) streams? Where do we get those?
Basic research is always interesting, but as Dr. Spencer says, being a cynic is an easy way to be right most of the time. And this one is very easy to be cynical about outside of the lab.
Alexander Pope wrote a great poem on a ridiculous subject. It is called “The Rape Of The Lock”. Or is it really a great poem? Can the sublime arise from a ridiculous premise? What purpose has poetry if it is just high sounding words about utterly inconsequential things?
But the argument can be made that in the poem, Pope, tongue in cheek, exposes the misdirected priorities and consequent utter uselessness of the British upper classes.
What of “carbon capture”? Is it “tongue in cheek”? By doing ridiculous science is the real agenda of the authors to expose the misdirected priorities and utter uselessness of a large part of the world’s “intellectual elite”? It has to be. No sane person could publish crap like this unless the true motivation was to expose the rot that has taken hold in our universities and institutions.
The authors are to be commended. One must look beneath their silly premise to behold the sublime accusation actually being made.
Eugene WR Gallun
The law of the Conservation of Energy be damned. The New Progressive Era is beginning.
Alas, another Tax Revenue scheme to be exploited.
There is a good case to be made for boosting CO2 emissions to increase Plant Growth, rain and agricultural output. There are scientifically proved links in this chain, unlike the wild spectualtion in CAGW and Water Vapour reinforced CO2 effects.
I guess you can take the Carbon and Oxygen discharge and then run it back through the power plant. And voila! Perpetual motion!…. or maybe not.
When, as a registered chemical engineer, I see press releases like this from supposedly trained engineers and scientists I immediately view the information with the following terms in mind.
“Pork Barrel addict”, “Scam artist”, “Incompetent idiot”, “Rent seeker”, “Grant abuser”, “Spineless coward”, “Publicity seeker”, “Spin doctor”.
I’m sure others trained in the real world application of the principles of thermodynamics, chemistry, heat transfer, mass transfer, reaction kinetics etc. could add a virtual Lexicon of terms to my abbreviated short list.
My carbon capture into electricity scheme still sounds more feasible.
The plan is to let the CO2 enter the atmosphere where some of it is converted into glucose and sugar, that is fed to hamsters, then the hamsters run on wheels to generate electricity. Now all we need are bigger hamsters.
Don’t take it serious, it’s meant as an exercise for students.
Very sad. Almost blithering idiocy. They do not deserve respect.
Look, there is a very direct way to do this, if “carbon sequestration” is an objective. Just equip a liquid air manufacturing plant onto a ship and go out into the briny deep. In comes air, cooled down to the sublimation point of carbon dioxide. Scrape off the dry ice and water ice on a continuous basis, and mix it into seawater which is pumped down several thousand feet. Where the CO2 can join with its fellows in the pools of the stuff that have been found on the sea bed.
But this is all nuts. The level of CO2 in the air is the result of an equilibrium between the oceans and the land, which for some reason has been steadily increasing. Those who have no understanding of chemistry cannot seem to grasp the idea of LeChatlier’s principle, which is that reaction rates will always ADJUST to maintain whatever the equilibrium condition is. This means that we can all stop producing CO2 tomorrow, and there should be little difference in the result. (It is interesting to note the annual ups and downs in the concentration trend, which roughly amounts to the “breathing” of the biosphere.)
How about we just plant 200 million tree’s…? Creates simplistic jobs for the uneducated (me). doesn’t cost 1.8 Trillion dollars AND the “greenies” could not possibly find anything to complain about…All of this can be done in the now unfrozen Canadian Shield…A massive area of uninhabited land that I’m sure Justin T. will be happy to donate to “Save The Planet” … .Whats that……it is still FROZEN ?? Well, I guess we have to wait a few more years until Canada gets a real Prime Minister that knows how to make a Frozen Tundra..ummm, unfrozen… ?..
Yosemite recently had a large fire. After St Helens blew millions of trees were planted.