
Ask HN: Does hobbyist-level C02 recapture make sense? - MuffinFlavored
https:&#x2F;&#x2F;news.ycombinator.com&#x2F;item?id=19842240<p>This post really interested me.<p>I asked a fellow HackerNews reader (Rod Fitzsimmons Frey) for his thoughts on the post. He kindly responded with the following outline of steps:<p>- Capture of CO2 from the atmosphere using a variety of techniques, usually adsorption (https:&#x2F;&#x2F;en.wikipedia.org&#x2F;wiki&#x2F;Carbon_capture_and_storage). This takes quite a bit of energy.<p>- Conversion of the dissolved CO2 into alcohols. Reaction is 2CO2 + 9H2O + 12e-  →  C2H5OH + 12OH- so it&#x27;s energy-uphill and needs an energy input. Maybe solar cells or a wind turbine. Requires a catalyst, often a variety of copper matrix. Catalysts are the major subject of research. To figure out whether you could do this in your garage you&#x27;d probably need to go to the literature.<p>- Distillation of the alcohols - usually done with heat, requires 800-900 deg C. Possible but hard and energy intensive. This is where Prometheus sits, they have a nanoscale membrane that does room-temperature separation of the alcohols using electricity input (more energy in!)<p>- Conversion of the alcohols into gasoline, diesel, kerosene etc. This is a pretty well-known process that uses a catalyst called ZSM-5 plus heat (mo&#x27; mo&#x27; energy!). I haven&#x27;t looked into the chemistry or the availability of the catalyst.<p>I think it&#x27;s pretty clear that... it&#x27;s most likely not possible to convert C02 into gasoline without using more energy + money than it would take to just go buy a $2.69&#x2F;gallon of 87 unleaded.<p>However, what is possible&#x2F;makes sense at a consumer level? In a modern day society where more and more individuals are learning the impact of climate change, I feel like any form of CO2 recapture + distillation would be a solid business idea from a &quot;demand&quot; standpoint.
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titojankowski
I like how you're thinking from a hobbyist standpoint.

The teaspoon analogy (below) is a little flawed. It discounts technology
improvement/growth.

You also have to include that:

1\. teaspoon tech is in its infancy

2\. if teaspoons were a few orders of magnitude cheaper and bigger, the job
would be done rapidly

3\. teaspoon tech has lots of promising pathways that haven't been followed

Carbon removal tech was $1,000/ton a few years ago, now it's ~$200/ton. Draw a
line through those points and you might get somewhere interesting.

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MuffinFlavored
What does a $200/ton carbon removal stack look like?

There's solar powered fans blowing air over some kind of material that
captures C02 out of the air. What exactly is that material, how much does it
cost, do consumers have easy access to it?

Then, you need immense heat to react the C02 in the material out, yeah? That's
part 2. I think if we focus on it one part at a time, we may get some answers!

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simonblack
That's a bit like believing you are capable of emptying the ocean with a
teaspoon.

By all means, go ahead. But excuse me for believing you will fail.

