Argonne National Lab Breakthrough Turns Carbon Dioxide into Ethanol | Hacker News Reader

Argonne National Lab Breakthrough Turns Carbon Dioxide into Ethanol

cleantechnica.com

61 pointskiyanwang18 comments

If anyone is interested I have found the press release directly from the Argonne National Laboratory: https://www.anl.gov/article/turning-carbon-dioxide-into-liqu...

And the related direct link to the paper: https://www.nature.com/articles/s41560-020-0666-x

This has to be energetically uphill, of course. How many units of energy do you have to put into get one unit of energy in ethanol form? Need numbers on this. Would it be a win to use wind energy during low price periods to make ethanol this way?

They say in the article that the conversion efficiency is 90%, which I assume means that if the reagent supply is infinite, 90% of the electrical energy you put into the catalyst is turned into chemical bond energy.

It says the Faradaic efficiency is 90%, which unfortunately is not the total energy efficiency. Total energy efficiency also includes thermodynamic and practical constraints.

https://en.wikipedia.org/wiki/Faraday_efficiency#Faradaic_lo...

However that's still a great figure.

I'm in awe that a carbon-substrate catalyst converts CO2 so well without degrading itself.

This is the kind of thing that could motivate big industry to get into carbon scrubbing, and maybe eventually cause it’s price to drop to levels where it outcompetes digging for oil.

This is going to be big. You can make solar more reliable by over building. Then you can use that sporadically surplus electricity to make liquid fuels - needed for aviation and handy for trains and trucks.

It seems very unlikely they'll be able to resist burning it, though.

With a twist of lime, they might just end up drinking it.

This is really cool! Since the ocean releases a good amount of CO2. Imagine pods sitting in the ocean capturing CO2 and using wave energy to generate ethanol..

Offshore wind could use this system too. It could be more efficient than the transmission loss.

This is an energy storage mechanism (in the form of combustable fuel), not a fuel-generation mechanism.

yes, exactly right, but a pretty exciting one. Combustible fuel can be stored for hours, days, weeks, months, and even years... unlike most forms of storing electricity.

A alcohol burning car could be carbon neutral, have great range, and be relatively cheap.

Presumably when the ethanol is burned, all the captured carbon is released again... So you have to re-capture each time you use it.

That's true, and the reason why we need healthy oceans and rain forests. They are carbon dioxide sinks and store carbon for eons.

Roughly speaking, if the carbon is captured from the atmosphere and later released into the atmosphere, the technology is carbon neutral.

If the carbon is sequestered (stored permanently) it is carbon negative.

If the carbon is obtained from an unsustainable source and released to the atmosphere it is carbon positive. The current consensus is that only carbon positive systems are considered a problem.

I did this in Alevel chemistry back in ~2001...

This comes across as kind of dismissive, as if the innovation here is just a realization that a well-known electrocatalytic reaction can be used for carbon sequestration. Am I reading your tone wrong?

The really hard bit in this kind of research is designing a catalyst that can mediate the reaction efficiently, doesn’t degrade rapidly, and isn’t prohibitively expensive to deploy at scale.

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