Solid Oxide Electrolyzer (SOXE) could solve global warming

[HawkII]

https://www.newsweek.com/device-that-turns-carbon-dioxide-oxygen-could-help-colonize-mars-1739040

 

Quote

It does so by first drawing the Martian air in through a filter that cleans it of contaminants. The air is then pressurized and sent through the Solid Oxide Electrolyzer (SOXE), an instrument developed and built by OxEon Energy, that electrochemically splits the carbon dioxide-rich air into oxygen ions and carbon monoxide.

The oxygen ions are then isolated and recombined to form breathable, molecular oxygen, or O2, which MOXIE then measures for quantity and purity before releasing it harmlessly back into the air, along with carbon monoxide and other atmospheric gases.

 

Imagine modifying this machine to turn CO2 into C & O2

Edited June 4, 2023 by HawkII
Extra info to entice and clarify. Gave this a better Title

[swansont]

The article says nothing about global warming.

[HawkII]

That's surprising. The potential is enormous. Acting on the CO2 directly seems a good solution

Edited June 4, 2023 by HawkII

[John Cuthber]

8 hours ago, HawkII said:

imagine modifying this machine to turn CO2 into C & O2

Under the right conditions you can get CO to decompose into CO2 and C.
https://en.wikipedia.org/wiki/Boudouard_reaction
Re-electrolyse the CO2 and, eventually,you will convert it all to C and O2.

The problem is (as ever) where to get the energy from.
 

[exchemist]

11 hours ago, HawkII said:

https://www.newsweek.com/device-that-turns-carbon-dioxide-oxygen-could-help-colonize-mars-1739040

 

 

Imagine modifying this machine to turn CO2 into C & O2

This is rather clever. It relies on certain metal oxides acting as conductors for oxide (O²⁻) ions in the solid state at high temperature.  At 800C, CO2 is reduced at a porous, nickel-based cathode, to CO and  O²⁻, the ions travelling, by means of ion vacancies in doped zirconium oxide, to the anode, where they give up 2 electrons and combine into O2. Details here: https://en.wikipedia.org/wiki/Mars_Oxygen_ISRU_Experiment

Neat, but indeed requires electrical energy to accomplish and generates carbon monoxide. As @John Cuthber points out, that would have to be disproportionated into C and CO2 in a further step, before it could be applied terrestrially. There are probably easier ways to convert CO2 to solids here on Earth, most of them biological and making use of sunlight rather than electricity.  

 

 

Edited June 5, 2023 by exchemist

[MigL]

I can see this method working on Earth ( aside from energy requirements ) as we only need to convert a couple of hundred parts per million of CO₂ to O₂ and CO.
But in the case of Mars, getting 20% O₂ in the atmosphere would also get you 20% CO.
Definitely not breathable.

[exchemist]

12 minutes ago, MigL said:

I can see this method working on Earth ( aside from energy requirements ) as we only need to convert a couple of hundred parts per million of CO₂ to O₂ and CO.
But in the case of Mars, getting 20% O₂ in the atmosphere would also get you 20% CO.
Definitely not breathable.

Yeah, it’s not for making a breathable atmosphere though, it’s as oxidiser for rocket fuel for the return journey. But in any case you can capture the oxygen separately at the anode and release the CO to the Martian atmosphere at the cathode.

[swansont]

8 hours ago, MigL said:

I can see this method working on Earth ( aside from energy requirements ) as we only need to convert a couple of hundred parts per million of CO₂ to O₂ and CO.
 

But having that much CO in earth’s atmosphere is problematic. Health issues start to appear above ~10 ppm

https://www.mcair.com/resources/carbon-monoxide-the-silent-killer#:~:text=0-9 ppm CO%3A no,the young and the elderly.

[MigL]

D'oh !
How Homer Simpson of me.
Forgot my CO detector is in ppm.

[Ken Fabian]

I don't think this will offer anything of significance for fixing global warming.

Does it require CO2 to be at high concentrations and or purity to work, ie separated from air or exhaust gases first? Where would the carbon go after? I note that the quantities are extremely large - 1 ppm is about 7 billion metric tons of atmospheric CO2 or 2.1  billion tons of Carbon. Global CO2 emissions are around the 40 billion per year mark.

Significantly, would the (clean) energy required to run it give better climate outcomes by extracting carbon from air than replacing fossil fuel use directly?

I am not a fan of Carbon Capture and Storage in - it doesn't address the principle problem (emissions from fossil fuel burning) and looks to me to be mostly promoted in order to NOT fix the dirty energy problem, by interests that won't care if it doesn't work.

[exchemist]

3 hours ago, Ken Fabian said:

I don't think this will offer anything of significance for fixing global warming.

Does it require CO2 to be at high concentrations and or purity to work, ie separated from air or exhaust gases first? Where would the carbon go after? I note that the quantities are extremely large - 1 ppm is about 7 billion metric tons of atmospheric CO2 or 2.1  billion tons of Carbon. Global CO2 emissions are around the 40 billion per year mark.

Significantly, would the (clean) energy required to run it give better climate outcomes by extracting carbon from air than replacing fossil fuel use directly?

I am not a fan of Carbon Capture and Storage in - it doesn't address the principle problem (emissions from fossil fuel burning) and looks to me to be mostly promoted in order to NOT fix the dirty energy problem, by interests that won't care if it doesn't work.

On the contrary, I think we should be looking at both approaches. They should not be seen as mutually exclusive alternatives. It seems to me we need all the help we can get, from any method that proves viable. Since the transition from fossil fuel will take at least a couple of decades to complete, we ought to pay some attention to what happens to the CO2 that the legacy uses will be producing over that time. But this particular idea is not intended for that and would almost certainly not be suitable.