8 ms·

Half a pound of this powder can remove as much CO2 from the air as a tree

21 points by lux 2y ago

lux 2y ago
Sharing this for the community's take on whether it has potential or is just another non-viable option.
- r2_pilot 2y ago
  It seems like it's a MOF amine approach which does have some benefits against the MEA used in submarines, such as lower corrosive properties potentially, lower heating requirements as you don't have to heat an aqueous solution, and it can be easier to discard the remnants once its co2 absorbing properties are diminished.
doctorwho42 2y ago
So it acts like a reusable CO2 trap, then releases said CO2 at the cost of heating it up to 140F. Which then releases it. It doesn't really talk about how you would sequester the gaseous CO2 other than "put it underground."... But if you put a gas underground it will eventually leak out. Even a liquid is prone to leak out eventually due to plate techtonics, but a liquid doesn't immediately turn into gaseous CO2. So though a crucial technology, I don't see how effective it would be in a long term solution.
- floxy 2y ago
  >how you would sequester the gaseous CO2 other than "put it underground." I wonder if there is a reason you couldn't just sequester the powder. Probably too expensive? Or not volume efficient? >to leak out eventually due to plate techtonics This might seem shortsighted, but I'm OK pushing the problem out by 50 million years or so.
  - BizarroLand 2y ago
    Since the powder is reusable, it likely wouldn't make sense to sequester it with the CO2 either materially or financially.
    - entropicdrifter 2y ago
      This. The powder is more efficiently used as a way to move the CO2 around than as a means to keep it sequestered.
      - Woodi 2y ago
        Still, tree produce oxygen from that CO_2. And do not need energy from grid for that :) Threating CO_2 like radioactive waste, putting it underground etc - that what I call not self-sustained :>
- BizarroLand 2y ago
  If you can extract ~100% pure CO2 from the powder, then it might be feasible to develop a process that can convert very dense CO2 into Carbon and Oxygen. Carbon is about 3/8ths of the total weight of a CO2 molecule and is solid and relatively inert at room temperature and pressure. Of course, if there were a convenient way to simply strip carbon off of a CO2 molecule to begin with that would be the ideal system, but I'm sure that can be figured out given enough opportunity. Plants do it, after all. It's not impossible.
  - jiggawatts 2y ago
    Plants do it using the energy from the sun. All of these “can’t we just unburn burnt things” forget that the reason we burnt the carbon in the first place was to get that energy. Unburning it would need to return that energy and more because of inefficiencies. If you have energy to spare, you don’t need to burn the carbon in the first place. With global fossil fuel usage still rising, we clearly don’t have any to spare.
    - glial 2y ago
      It's not so clear to me -- the MIT Technology Review is already wringing its hands about energy being so cheap it causes problems with economics. [1] https://www.technologyreview.com/2021/07/14/1028461/solar-value-deflation-california-climate-change/ https://www.technologyreview.com/2021/07/14/1028461/solar-va...
      - doctorwho42 2y ago
        Energy can be economically cheap in the current paradigm, while also being insufficiently cheap or insufficient quantities of clean energy to make the above comments suggestion work.
  - gus_massa 2y ago
    > Plants do it, after all. It's not impossible. The problem is that to reverse CO2 -> C + O2 you need the same amount of energy that you get burning coal C + O2 -> CO2. But burning coal, like half of the energy is lost as unuseful heat. The reaction of plants is different, but plants only has a 2% of efficiency. The chemical reaction of plants is more complicated, so let's be optimistic and assume this reaction has a 10% of efficiency. If they use a coal plant to power the CO2 -> C + O2 conversion, they will release like 20 times the amount of CO2 absorbed. If they use a renewable source, it's better to close the absortion plant and also 20 coal plants. Until we close all the coal plants and we get very cheep carbon-free energy, it's bad for the environment to try a CO2 -> C + O2 conversion.
- jjk166 2y ago
  Many common minerals like olivine react with CO2 at high concentrations to form carbonates which are geologically stable. The issue is getting the high carbon concentrations to make this process fast. Concentrating CO2 is the major technical hurdle of carbon sequestration.
- 7speter 2y ago
  What I'm about to say may sound absurd and an attempt to be funny, but I'm being serious. The other day I was wondering how people always talk about sending undesirable material (garbage, spent radioactive fuel, etc.) on a one way trip to the sun. Why not send things to the surface of Venus? It has an ultra dense atmosphere that pulverizes anything that reaches the surface. In the case of this material, it's just more C02, which is what the atmosphere of Venus is already primarily composed of. We aren't going to ever explore the surface of Venus, or at least we won't for thousands, if not millions of years, barring we can easily convert co2 into energy, so is this a bad idea?
  - defrost 2y ago
    Let's take the 2020 figures for annual human carbon dioxide emmissions. 35 billion metric tons. What's your back of the envelope energy figure for extracting that weight of a gas from the atmosphere, pressurising it, and lifting it to orbit and sending it to Venus? Got a rough notion of the number of trips, fuel and resources that would need every single year?
tredre3 2y ago
Might be cool to have this in an office or school classes. I realize that proper ventilation is the real fix, but it's not realistic to rebuild all buildings. Just think about it, you have a decorative box in your office that absorbs CO2, would it slow the inevitable cognitive decline that happens when you close your door in your poorly ventilated room?
- _yb2s 2y ago
  I suspect that previously acceptable building designs now cause cognitive decline because of much higher outdoor CO2 levels- it’s a bigger problem than people realize. I live in a mild climate where I can just keep the windows open year round- but when the neighbors have a loud party I close them to focus or sleep and CO2 will quickly climb to over 2000ppm, well over the 1400 or so that causes measurable negative effects. I suspect most people in climates that require heating or cooling are almost permanently experiencing reduced cognition and might not know.
  - kadoban 2y ago
    This is definitely a real problem, but it's not caused by higher outdoor CO2 levels. The levels outside are typically in the 400-500ppm range. When you're enclosed with not enough ventilation, the issue is you (and other breathing organisms) and the lack of ventilation, not the outdoor level. The outdoor level has absolutely risen, it's just not the important factor here. You're very lucky that you can keep windows open so often. My climate makes that impossible for much of the year; I'm looking in to getting an ERV installed asap.
    - _yb2s 2y ago
      I disagree- many people, especially in Europe are still using buildings designed in pre-industrial times, when CO2 levels were as low as half what they are in urban areas now. Those buildings now will have much higher CO2 levels indoors than when first built, with the same amount of air exchange. One could estimate exactly how much higher with some differential equations, but certainly in some cases it is possible to push things over the limit where there are now problems, everything else remaining the same. Moreover, those buildings likely now have much less air exchange than when designed now that they use AC instead of open windows, forced air heat instead of unsealed fireplaces (which turn over a lot of air), and possibly have been updated to more airtight doors and windows.
LorenDB 2y ago
https://archive.ph/JPmvj https://archive.ph/JPmvj
kazinator 2y ago
> As it entered the tube, the Berkeley air contained CO2 in concentrations ranging from 410 ppm to 517 ppm. When it came out the other side, the scientists could not detect any carbon dioxide at all, Zhou said. This sounds like it could be the basis for a respirator-like breathing apparatus, not requiring tanks, for entering and staying in enclosed spaces where the concentration of CO2 is high. (Provided there is enough oxygen.)
- hansvm 2y ago
  That feels super dangerous. CO2 is mostly fine to breathe, but it triggers the impulse to breathe. Without it you won't feel that you're running out of oxygen.
  - eszed 2y ago
    With real-time detection (I'd expect that exists, but don't know for sure) you can divert some of the airstream through this scrubber to target a particular concentration of CO2.
    - telgareith 2y ago
      You don't need any CO2. Oxygen bottle, co2 scrubber, pure oxygen purge prior to diving... and you've got yourself a rebreather. https://en.m.wikipedia.org/wiki/Rebreather https://en.m.wikipedia.org/wiki/Rebreather
  - surfpel 2y ago
    That's CO2 IN the blood that "triggers breathing". Unless you plan to inject the powder, that's not really an issue.
    - deleted 2y ago
      [deleted]
    - hansvm 2y ago
      What I mean is that scrubbing the CO2 leaves you in a scenario where the air is just as dangerous as before (no oxygen) but you don't have any reflexes or senses letting you know of the danger.
ZeroGravitas 2y ago
I think that I shall never see A half a pound of powder as lovely as a tree. -- Joyce Kilmer
Ancalagon 2y ago
Wondering how inert and/or toxic this stuff is. Could you mass produce it and just sprinkle it across the arctic? Sequester carbon and have it locked up in the permafrost.

21 points by lux 2y ago

lux 2y ago

Sharing this for the community's take on whether it has potential or is just another non-viable option.

r2_pilot 2y ago
It seems like it's a MOF amine approach which does have some benefits against the MEA used in submarines, such as lower corrosive properties potentially, lower heating requirements as you don't have to heat an aqueous solution, and it can be easier to discard the remnants once its co2 absorbing properties are diminished.

doctorwho42 2y ago

So it acts like a reusable CO2 trap, then releases said CO2 at the cost of heating it up to 140F. Which then releases it. It doesn't really talk about how you would sequester the gaseous CO2 other than "put it underground."... But if you put a gas underground it will eventually leak out. Even a liquid is prone to leak out eventually due to plate techtonics, but a liquid doesn't immediately turn into gaseous CO2. So though a crucial technology, I don't see how effective it would be in a long term solution.

floxy 2y ago
>how you would sequester the gaseous CO2 other than "put it underground." I wonder if there is a reason you couldn't just sequester the powder. Probably too expensive? Or not volume efficient? >to leak out eventually due to plate techtonics This might seem shortsighted, but I'm OK pushing the problem out by 50 million years or so.
- BizarroLand 2y ago
  Since the powder is reusable, it likely wouldn't make sense to sequester it with the CO2 either materially or financially.
  - entropicdrifter 2y ago
    This. The powder is more efficiently used as a way to move the CO2 around than as a means to keep it sequestered.
    - Woodi 2y ago
      Still, tree produce oxygen from that CO_2. And do not need energy from grid for that :) Threating CO_2 like radioactive waste, putting it underground etc - that what I call not self-sustained :>
BizarroLand 2y ago
If you can extract ~100% pure CO2 from the powder, then it might be feasible to develop a process that can convert very dense CO2 into Carbon and Oxygen. Carbon is about 3/8ths of the total weight of a CO2 molecule and is solid and relatively inert at room temperature and pressure. Of course, if there were a convenient way to simply strip carbon off of a CO2 molecule to begin with that would be the ideal system, but I'm sure that can be figured out given enough opportunity. Plants do it, after all. It's not impossible.
- jiggawatts 2y ago
  Plants do it using the energy from the sun. All of these “can’t we just unburn burnt things” forget that the reason we burnt the carbon in the first place was to get that energy. Unburning it would need to return that energy and more because of inefficiencies. If you have energy to spare, you don’t need to burn the carbon in the first place. With global fossil fuel usage still rising, we clearly don’t have any to spare.
  - glial 2y ago
    It's not so clear to me -- the MIT Technology Review is already wringing its hands about energy being so cheap it causes problems with economics. [1] https://www.technologyreview.com/2021/07/14/1028461/solar-value-deflation-california-climate-change/ https://www.technologyreview.com/2021/07/14/1028461/solar-va...
    - doctorwho42 2y ago
      Energy can be economically cheap in the current paradigm, while also being insufficiently cheap or insufficient quantities of clean energy to make the above comments suggestion work.
- gus_massa 2y ago
  > Plants do it, after all. It's not impossible. The problem is that to reverse CO2 -> C + O2 you need the same amount of energy that you get burning coal C + O2 -> CO2. But burning coal, like half of the energy is lost as unuseful heat. The reaction of plants is different, but plants only has a 2% of efficiency. The chemical reaction of plants is more complicated, so let's be optimistic and assume this reaction has a 10% of efficiency. If they use a coal plant to power the CO2 -> C + O2 conversion, they will release like 20 times the amount of CO2 absorbed. If they use a renewable source, it's better to close the absortion plant and also 20 coal plants. Until we close all the coal plants and we get very cheep carbon-free energy, it's bad for the environment to try a CO2 -> C + O2 conversion.
jjk166 2y ago
Many common minerals like olivine react with CO2 at high concentrations to form carbonates which are geologically stable. The issue is getting the high carbon concentrations to make this process fast. Concentrating CO2 is the major technical hurdle of carbon sequestration.
7speter 2y ago
What I'm about to say may sound absurd and an attempt to be funny, but I'm being serious. The other day I was wondering how people always talk about sending undesirable material (garbage, spent radioactive fuel, etc.) on a one way trip to the sun. Why not send things to the surface of Venus? It has an ultra dense atmosphere that pulverizes anything that reaches the surface. In the case of this material, it's just more C02, which is what the atmosphere of Venus is already primarily composed of. We aren't going to ever explore the surface of Venus, or at least we won't for thousands, if not millions of years, barring we can easily convert co2 into energy, so is this a bad idea?
- defrost 2y ago
  Let's take the 2020 figures for annual human carbon dioxide emmissions. 35 billion metric tons. What's your back of the envelope energy figure for extracting that weight of a gas from the atmosphere, pressurising it, and lifting it to orbit and sending it to Venus? Got a rough notion of the number of trips, fuel and resources that would need every single year?

tredre3 2y ago

Might be cool to have this in an office or school classes. I realize that proper ventilation is the real fix, but it's not realistic to rebuild all buildings. Just think about it, you have a decorative box in your office that absorbs CO2, would it slow the inevitable cognitive decline that happens when you close your door in your poorly ventilated room?

_yb2s 2y ago
I suspect that previously acceptable building designs now cause cognitive decline because of much higher outdoor CO2 levels- it’s a bigger problem than people realize. I live in a mild climate where I can just keep the windows open year round- but when the neighbors have a loud party I close them to focus or sleep and CO2 will quickly climb to over 2000ppm, well over the 1400 or so that causes measurable negative effects. I suspect most people in climates that require heating or cooling are almost permanently experiencing reduced cognition and might not know.
- kadoban 2y ago
  This is definitely a real problem, but it's not caused by higher outdoor CO2 levels. The levels outside are typically in the 400-500ppm range. When you're enclosed with not enough ventilation, the issue is you (and other breathing organisms) and the lack of ventilation, not the outdoor level. The outdoor level has absolutely risen, it's just not the important factor here. You're very lucky that you can keep windows open so often. My climate makes that impossible for much of the year; I'm looking in to getting an ERV installed asap.
  - _yb2s 2y ago
    I disagree- many people, especially in Europe are still using buildings designed in pre-industrial times, when CO2 levels were as low as half what they are in urban areas now. Those buildings now will have much higher CO2 levels indoors than when first built, with the same amount of air exchange. One could estimate exactly how much higher with some differential equations, but certainly in some cases it is possible to push things over the limit where there are now problems, everything else remaining the same. Moreover, those buildings likely now have much less air exchange than when designed now that they use AC instead of open windows, forced air heat instead of unsealed fireplaces (which turn over a lot of air), and possibly have been updated to more airtight doors and windows.

LorenDB 2y ago

https://archive.ph/JPmvj https://archive.ph/JPmvj

kazinator 2y ago

> As it entered the tube, the Berkeley air contained CO2 in concentrations ranging from 410 ppm to 517 ppm. When it came out the other side, the scientists could not detect any carbon dioxide at all, Zhou said. This sounds like it could be the basis for a respirator-like breathing apparatus, not requiring tanks, for entering and staying in enclosed spaces where the concentration of CO2 is high. (Provided there is enough oxygen.)

hansvm 2y ago
That feels super dangerous. CO2 is mostly fine to breathe, but it triggers the impulse to breathe. Without it you won't feel that you're running out of oxygen.
- eszed 2y ago
  With real-time detection (I'd expect that exists, but don't know for sure) you can divert some of the airstream through this scrubber to target a particular concentration of CO2.
  - telgareith 2y ago
    You don't need any CO2. Oxygen bottle, co2 scrubber, pure oxygen purge prior to diving... and you've got yourself a rebreather. https://en.m.wikipedia.org/wiki/Rebreather https://en.m.wikipedia.org/wiki/Rebreather
- surfpel 2y ago
  That's CO2 IN the blood that "triggers breathing". Unless you plan to inject the powder, that's not really an issue.
  - deleted 2y ago
    [deleted]
  - hansvm 2y ago
    What I mean is that scrubbing the CO2 leaves you in a scenario where the air is just as dangerous as before (no oxygen) but you don't have any reflexes or senses letting you know of the danger.

ZeroGravitas 2y ago

I think that I shall never see A half a pound of powder as lovely as a tree. -- Joyce Kilmer

Ancalagon 2y ago

Wondering how inert and/or toxic this stuff is. Could you mass produce it and just sprinkle it across the arctic? Sequester carbon and have it locked up in the permafrost.