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Carbon dioxide capture from open air using covalent organic frameworks

nature.com

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Re: Carbon dioxide capture from open air using covalent organic frameworks

#51

Post by lm28469 »

bryanlarsen wrote: post #45
lm28469 wrote: post #42

Earlier quoted context omitted.

> switching to zero-carbon electricity and zero-carbon transportation would lower carbon emissions by 60% Is the 0 carbon mining and 0 carbon steel in the room with us right now ? What about the 0 carbon asphalt ? 0 carbon tires ? 0 carbon cement to build your 0 carbon power plant ? 0 carbon plastic to build your 0 carbon solar panels ? fyi steel is still made with coke, 1700s century style, and nothing is even close…

IMO, my solution is far less simple and hand-wavy than yours is. I can point to several books with solutions on how to get from my 60% solution to a full zero-carbon future. There is no degrowth based path that gets us to 0 carbon except for degrowth to 0 humans.

Meanwhile, after decades of "we tried everything" we produce, year after year, record levels of co2

You can look at it any way you want it simply doesn't work, it's not enough to wish for it.

There is no 60% solution, not even close, so it doesn't matter if a sci fi books mention a 0 carbon future

Re: Carbon dioxide capture from open air using covalent organic frameworks

#52

Post by lm28469 »

ryandvm wrote: post #46
lm28469 wrote: post #36

Earlier quoted context omitted.

> Degrowth doesn't work either It's literally the only mathematically viable option. Either you choose it and plan for it or you hit the wall and deal with the consequences. Just take a gpd per capita world map, superimpose it over a pollution per capita world map, and extrapole the impact of china+india+africa living like the average american or even the average european, it just doesn't work out, but it's coming ve…

It's not coming very soon because those populations are going to completely skip the phase where every household has 2 or 3 fossil fuel vehicles.

Personal transportation is about 15% of co2 emissions. That hardly explains why the average American lifestyle produces literally 10 times more co2 than the average Indian's

Re: Carbon dioxide capture from open air using covalent organic frameworks

#53

Post by Gibbon1 »

pfdietz wrote: post #12
lez wrote: post #2

I think such an appliance had already been invented. They are called "trees". All they need to do their work is corporations leaving them alone.

Until you do the math, then you see how bad a solution trees are. It's the same reason biofuels cannot be a general replacement for fossil fuels. Growing trees is nice for other reasons, of course, and some limited CO2 capture would come along for the ride. This would not eliminate the desirability of other kinds of CO2 capture.

I harp on this. Unless I biffed my calcs a solar farm produces 25-50 times as much energy per acre as corn. That alone tells you biofuels is a dead technology.

A solar farm doesn't need to be weeded, ploughed, planted, weeded again, topped, and harvested every year like corn does. You also don't need to ferment it to ethanol then burn it at a 70% loss to power a set of wheels.

Possible also that the vegetation growing between and under the panels sequesters carbon.

Re: Carbon dioxide capture from open air using covalent organic frameworks

#54

Post by OutOfHere »

danbruc wrote: post #25
mapt wrote: post #19

Earlier quoted context omitted.

This. We have a worked example for geologically stable carbon sequestration without any novel chemical bonding, and that's storing carbon in compounds that are mostly unhydrogenated carbon by mass, deep underground: Charcoal. If you aim to sequester carbon without some kind of reactant (and most reactants are incredibly energy intensive to make & stage, burning more CO2 than captured), you have to effectively make ch…

There is not nearly enough available space on the surface of Earth to make any dent into the atmospheric carbon dioxide concentration over any relevant time frame. We burnt through millions of years of sequestrated carbon in a century and some, but we do not have millions of years to do the sequestration again.

If we solve fusion, or even if we exploit space solar on a massive scale, we should in principle have all the energy we need to put the carbon back into charcoal.

Re: Carbon dioxide capture from open air using covalent organic frameworks

#55

Post by bryanlarsen »

lm28469 wrote: post #51
bryanlarsen wrote: post #45

Earlier quoted context omitted.

IMO, my solution is far less simple and hand-wavy than yours is. I can point to several books with solutions on how to get from my 60% solution to a full zero-carbon future. There is no degrowth based path that gets us to 0 carbon except for degrowth to 0 humans.

Meanwhile, after decades of "we tried everything" we produce, year after year, record levels of co2 You can look at it any way you want it simply doesn't work, it's not enough to wish for it. There is no 60% solution, not even close, so it doesn't matter if a sci fi books mention a 0 carbon future

CO2 levels have been dropping on a per capita basis for several years and are expected to drop on an absolute basis in 2024 or 2025.

Re: Carbon dioxide capture from open air using covalent organic frameworks

#56

Post by danbruc »

OutOfHere wrote: post #54
danbruc wrote: post #25

Earlier quoted context omitted.

There is not nearly enough available space on the surface of Earth to make any dent into the atmospheric carbon dioxide concentration over any relevant time frame. We burnt through millions of years of sequestrated carbon in a century and some, but we do not have millions of years to do the sequestration again.

If we solve fusion, or even if we exploit space solar on a massive scale, we should in principle have all the energy we need to put the carbon back into charcoal.

Sure, with enough energy we can do whatever we want, but we just do not have enough clean energy, that is the very problem carbon capture is supposed to address.

Re: Carbon dioxide capture from open air using covalent organic frameworks

#57

Post by pfdietz »

Gibbon1 wrote: post #53
pfdietz wrote: post #12

Earlier quoted context omitted.

Until you do the math, then you see how bad a solution trees are. It's the same reason biofuels cannot be a general replacement for fossil fuels. Growing trees is nice for other reasons, of course, and some limited CO2 capture would come along for the ride. This would not eliminate the desirability of other kinds of CO2 capture.

I harp on this. Unless I biffed my calcs a solar farm produces 25-50 times as much energy per acre as corn. That alone tells you biofuels is a dead technology. A solar farm doesn't need to be weeded, ploughed, planted, weeded again, topped, and harvested every year like corn does. You also don't need to ferment it to ethanol then burn it at a 70% loss to power a set of wheels. Possible also that the vegetation growin…

And the solar farm doesn't transpire quite the enormous quantities of water a field of corn does. So much water goes into the air from a corn field it affects the weather.

I wouldn't say biofuels are a dead technology, but they are niche. They may be useful in a post-fossil fuel age for things that are very difficult to electrify, like long distance air travel and production of organic chemical feedstocks.

Re: Carbon dioxide capture from open air using covalent organic frameworks

#58

Post by OutOfHere »

danbruc wrote: post #56
OutOfHere wrote: post #54

Earlier quoted context omitted.

If we solve fusion, or even if we exploit space solar on a massive scale, we should in principle have all the energy we need to put the carbon back into charcoal.

Sure, with enough energy we can do whatever we want, but we just do not have enough clean energy, that is the very problem carbon capture is supposed to address.

It would be completely disingenuous to use carbon capture as an excuse to continue the use of fossil fuels. Firstly, it will be so price inefficient. Secondly, it delays the inevitable, meaning the transition to clean energy, as some European countries already have accomplished.

The demand for carbon capture makes more sense after we have already transitioned to clean energy, as we can then begin to reverse the damage that excess CO2 and methane have been causing. The financial model for doing this is by a long-acting insurance firm that not only collects insurance but also uses the premium to preemptively take restorative actions.

Re: Carbon dioxide capture from open air using covalent organic frameworks

#59

Post by danbruc »

OutOfHere wrote: post #58
danbruc wrote: post #56

Earlier quoted context omitted.

Sure, with enough energy we can do whatever we want, but we just do not have enough clean energy, that is the very problem carbon capture is supposed to address.

It would be completely disingenuous to use carbon capture as an excuse to continue the use of fossil fuels. Firstly, it will be so price inefficient. Secondly, it delays the inevitable, meaning the transition to clean energy, as some European countries already have accomplished. The demand for carbon capture makes more sense after we have already transitioned to clean energy, as we can then begin to reverse the damag…

Carbon capture is of course less efficient than not burning fossil fuels to begin with, so the first goal must be to no longer emit new carbon. Then it may make sense to capture some carbon and turn it into synthetic fuels for certain applications because of the energy density and ease of storage. Maybe even for plastics and similar stuff. After that, undoing a century of emissions, that is a monumental challenge. Depending on how exactly we want to store the carbon, we might need more or less the same amount of energy that we got out of fossil fuels over the last century. Double our renewable energy generation capacity and then use half of it for half a century - roughly taking into account the increase in emissions over the past century - to capture carbon.

Re: Carbon dioxide capture from open air using covalent organic frameworks

#60

Post by mapt »

danbruc wrote: post #56
OutOfHere wrote: post #54

Earlier quoted context omitted.

If we solve fusion, or even if we exploit space solar on a massive scale, we should in principle have all the energy we need to put the carbon back into charcoal.

Sure, with enough energy we can do whatever we want, but we just do not have enough clean energy, that is the very problem carbon capture is supposed to address.

So...

No.

That's almost certainly a dumb idea. Always was. A red herring from the fossil fuel companies.

Obviously digging 1000kg of coal out of the ground, burning it to make electricity, and using that electricity to _synthetically create more coal_, and putting that back deep underground, is not going to put away even 100kg of carbon; You're probably lucky if you get 10kg given that CO2 is a trace gas.

You can do it cheaper, if you're willing to tolerate the carbon having less than the geological stability of coal. But then the ground burps and you're back to square one.

The part of carbon sequestration that isn't insultingly is the question of what happens once we've destroyed all the fossil fuel infrastructure and replaced that part of our civilization with renewables and (since it's always going to be advantageous to be a free rider) a good number of bomb craters.

My suspicion is that even when we get to that point, sequestration of 1kg is _so much more difficult_ than emission of 1kg was, that there's still a vast gulf between being at that point, and the point where we have the excess resources sufficient to sequester significant portions of the atmospheric carbon artificially. Probably instead, we end up coasting for a long while to see how much the biosphere can put away on its own; If we have climate change issues, we deal with them via stratospheric sulfur injection and by stochastically just adapting our footprint on the planet.

But I'm willing to be persuaded on this point. Perhaps there's work to be done with some kind of advantageous catalyst, mineral reserve & reaction (olivine maybe?), some way to cheat the system in the long run. I just don't think it's especially relevant to our plight in the short term.

The point is, charcoal production is the default method of carbon sequestration, the reliable null hypothesis by which you have to measure any other method, the denominator of human effort in this venture. No, even charcoaling the entire Earth's forests is nowhere close to sufficient to offset coal production (how the fuck could it be? The Carboniferous epoch was 60 million years long and we're going to run through its detritus in less than 600 years!), but a project to run a country-sized forest through the oven and into the mines every year is the _baseline_ for future meaningful effort.

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