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CO2 To Ethanol In One Step With Cheap Catalyst (sciencedaily.com)
Reader networkBoy writes: Boffins at ORNL (Department of Energy's Oak Ridge National Laboratory) have discovered a simple and cheap catalyst that can take CO2 (Carbon Dioxide) dissolved in solution with water and at room temperature convert it to ethanol with 60%+ yields. They envision it as a way to store surplus power from green energy plants and then burning it to fill in lulls in supply.From the report:The team used a catalyst made of carbon, copper and nitrogen and applied voltage to trigger a complicated chemical reaction that essentially reverses the combustion process. With the help of the nanotechnology-based catalyst which contains multiple reaction sites, the solution of carbon dioxide dissolved in water turned into ethanol with a yield of 63 percent. Typically, this type of electrochemical reaction results in a mix of several different products in small amounts. "We're taking carbon dioxide, a waste product of combustion, and we're pushing that combustion reaction backwards with very high selectivity to a useful fuel," Rondinone said. "Ethanol was a surprise -- it's extremely difficult to go straight from carbon dioxide to ethanol with a single catalyst."
By law, boffintry can only be granted to citizens of the UK.
love is just extroverted narcissism
"It's almost as if you posted that without reading the article summary..."
You must be new here, welcome.
Which efficiency?
Energy use wise, or product synthesis wise?
The summary gives the latter at just over 60%.
The former? Who knows?
I am more interested in how sensitive to poisoning the catalyst is. Would exposure to salt water damage it, for instance.
If not, then huge installations of these in the open ocean coupled with tidal force generators or wave mechanic generators for the electrical power needed could make drilling for oil obsolete, while simultaneously directly removing the cause of ocean acidification. Win win.
I guess we need to get Universal Basic Income ready for all the Yeasts we're going to be putting out of business with this new technology....
Light travels faster than sound. This is why some people appear bright until you hear them speak.........
Here's a link to the actual paper.
(Since the editors won't do it.)
The catalyst looks pretty good. I'd be interested to see how long it lasts - some catalysts become poisoned by impurities in the source gasses, and lose effectiveness over time.
The paper mentions copper oxide forming on the copper nanoparticles due to transport in the air to the test equipment. That probably means that the catalyst might lose effectiveness due to dissolved oxygen in the water.
Any actual chemists care to comment?
So what happens to the other 37 procent? If you keep adding CO2 to the water, re-saturating it, doesn't the reaction just keep going?
That's faradic efficiency. The remaining 37% go to heat, and perhaps other by-products.
The paper points out that CO, H2, and CH4 are made at various other voltages, maybe some of the remaining 37% is in useful by-products.
(I've only skimmed the paper - need more time to read and digest.)
"Catalyst" means it isn't directly expended in the reaction. So the cost of a catalyst doesn't particularly matter. That's why there's platinum currently catalyzing your engine exhaust into CO2.
For this reaction, you need BOTH CO2 (from burning fossil fuels) AND "free energy" (noon solar on cloudless days).
The otherwise wasted energy from the unreliable renewable sources is used to convert CO2 into fuel.
The summary is misleading; a look at the paper reveals the 63% is the Faradic efficiency, at a current of -1.2 volts.
Er, I don't know how "at a current of" slipped in there. Volts are voltage, not current.
Vodka is one thing but this has the potential to convert weak fizzy beer into strong silent stuff. A true advance for mankind...
The catalyst is not consumed in the reaction but the catalyst most certainly can be affected by a reaction. If you don't believe me then explain why fuel cell poisoning isn't real.
The price of the catalyst is also most certainly important too.
AntiFA: An abbreviation for Anti First Amendment.
To collect the ethanol, the water being treated needs to be isolated from the rest of the reactant supply (aka, the ocean). The availability of local power from ocean wave generators, or tidal generators means the expense of using reverse osmosis is possible to account for. We don't need a membrane that makes clean water, just one that holds ethanol in, and that keeps plankton and microbes out.
Ethanol is a fairly large molecule (compared to salt, or co2), and microbes are downright huge in comparison.
Automated jets of ocean water against the membrane to knock plankton off every so often, coupled with a maintenance schedule, and such platforms could be extracting ethanol in huge amounts cheaply, expelling very clean ocean brine.
Assuming the catalyst can endure salt being present anyway.
That probably depends mostly on how you get your electricity. Wind or Solar are likely carbon negative, Coal is almost certainly carbon positive.
I read the internet for the articles.
"Why should I listen to someone that doesn't know the difference between affect and effect?"
I don't know. However, since I used "affected" correctly that statement has nothing to do with my post.
AntiFA: An abbreviation for Anti First Amendment.
His/her question is good, and the summary is incomplete. It converts CO2 to CH3CH2OH at a yield of about 63%, but what CO2 concentration in the water are they assuming? Average soda concentration is about 0.12-0.15 M (moles per liter) at about 4 bar. That would mean you'd get 0.05 M alcohol (2 carbons per EtOH from one carbon in CO2, 0.5*0.63*0.15), which is 0.05 moles EtOH/55.5 moles water or about 0.08 percent alcohol by volume. That's a lot less than the ethanol conversion you'd get from corn.
It did not mention the catalyst materials cost, nor the materials processing required to make a nanomaterial.
So we'd have energy costs by compressing CO2, then converting it using the catalyst, then there would be ethanol separation costs (with requisite electricity/natural gas from the distillation columns) from water that far exceed normal ethanol separation, and the ethanol would still have about 10% water because it is an azeotrope,so then you'd need another liquid-liquid extraction...
As is the case with the other carbon dioxide conversion schemes, it's really cool chemistry, looks good in summary, but the details render it ineffective for practical use.
"Who are you?" "No one of consequence." "I must know." "Get used to disappointment."
Hmm, it seems the laws of thermodynamics are being overlooked here...
Nah, we don't normally care if yeast die by the billions, and they're exceedingly unlikely to initiate an armed revolt to avoid starving to death.
--- Most topics have many sides worth arguing, allow me to take one opposite you.
They should fund a startup ("carbonol.io") and Kickstarter a giant oceangoing ethanol mining drone, then lobby world governments to prevent further carbon emission cuts so as to protect their business model.
They already do this at some power generation stations (e.g., [1] from 2014). There may possibly be issues with suphur poisoning though.
[1] https://www.theguardian.com/en...
even if the catalyst wasn't poisoned, a biofilm would clog those activity sites in an open body of water.
Intuition tells me that ethanol should destroy the biofilm. Research tells me otherwise. It actually seems to encourage it.
https://www.ncbi.nlm.nih.gov/p...
However, as hankwang mentioned, bacteria doesn't do so well in elecrolyzed water.
https://www.sciencedaily.com/r...
Algae might not be safe either:
https://www.ncbi.nlm.nih.gov/p...
With Mars having a 96% Co2 atmosphere, it seems like this technology would be a dream come true for the first human explorers to Mars.
Elon Musk said that the first visitors would have to build a propellant plant and it would take many months to make their own fuel for the return journey. I wonder how significantly this technology and the abundance of Martian CO2 would speed that up?
No. Wind and solar are NOT carbon-negative.
And it is REALLY simple to prove:
1. They don't consume CO2 to produce energy
2. End
And if you use coal/petrol to produce any part of the turbines/panels in any stage of the production they will be carbon positive.
But what really matters here is not that they are carbon positive, it is that they produce so little carbon when compared to all other sources that it doesn't really matters...In the end, they are displacing something hugely worse so they are a net positive.
It's a flavor of an obscure Germanic language spoken by a large portion of the civilized people in this place called 'America.' You may have heard of it. We're renowned for our trucks and our elevators, as well for as our scientists and engineers. No boffins though.
The main problem is that the sun does not produce a whole lot of energy that can be captured on the night side of the earth, and we happen to consume a lot of energy when it's dark. If you overbuild capacity for daytime generation, nighttime generation is mostly solved, the big problem now is not cheap renewable energy, but rather, how to store it. Even if converting water and CO2 in to Ethanol is only 15% efficiency, you're still able to store 15% of your excess grid energy, whereas before you could only store 0% of excess grid energy. These guys are claiming 60% in the lab, which probably means 20-30% at industrial scale, perhaps 40% within our lifetime. It's not 85-90% hydro-electric efficient, but that's pretty dang good for a fuel which has so many uses, stores well for long periods of time and works with existing combustion engines.
moox. for a new generation.
So would I, apparently.
Live in a State that mandates a silly low alcohol content for your beer? Drop in the catalyst, hook it to a battery and voila! Problem solved.
As I read it, TFA _does_ give a clue as to efficiency.
60% of the electrons are used for producing ethanol.
Equilibrium potential for the ethanol reaction is 84 mV.
The total voltage that is used is 1.2V, which is 14 times as high.
That means that only 7% of the voltage is used effectively.
This gives a total energy of a little over 4%.
In the conclusion, this is mentioned as "The overpotential (which might be lowered with the proper electrolyte, and by separating the hydrogen production to another catalyst) probably precludes economic viability for this catalyst"
So, they don't (dare to) mention efficiency directly, but data is presented by which it can be calculated.