4 ms·

I'm doubtful this is truly eco friendly. The quantities produced are so small that the energy costs of the sprayer system and catalyst become very high. Global

I'm doubtful this is truly eco friendly. The quantities produced are so small that the energy costs of the sprayer system and catalyst become very high. Global production of ammonia is around 4 tonnes per second whereas this process produces 0.005g/m2 per second so you would need 800 square kms of catalyst to meet global demand (around the same area as Singapore).

usrusr 3y ago
Strong too good to be true vibes. Ammonia is an energy carrier, and in the conventional process that energy comes from H2. Atmospheric nitrogen and water are some of the most inert compounds in existence and that difference has to come from somewhere. Perhaps they just haven't identified the voltage or radiation yet? In a lab setting with an output that extrapolates to 0.005g/m2s, there can be a lot of inputs you just haven't successfully ruled out.
- pjc50 3y ago
  I'm guessing it's just endothermic, and relies on the energy probability distribution on these droplets to have some atoms of high enough energy to react.
- opportune 3y ago
  I did a deep dive in seeing how this is even possible, because it shouldn’t be thermodynamically, and it seems like all this “microdroplets allow for seemingly impossible reactions by spontaneously forming peroxide” is actually caused by ozone per some researchers: https://cen.acs.org/research-integrity/reproducibility/Claims-water-turning-hydrogen-peroxide/100/web/2022/05 https://cen.acs.org/research-integrity/reproducibility/Claim... This seems to be an open debate topic in chemistry. But I think it’s basically the case that, everybody knows it has to be ozone because the energy must be coming from somewhere, but knowing it’s ozone makes the dependent studies like this uninteresting (saying “who knows how we seemingly produced ammonia with little power, maybe this will cure climate change” gets your papers a lot more citations and recognition than “there is enough ozone in the air to produce small quantities of peroxide to use in reactions at STP”). Until it’s conclusively debunked people are gonna landgrab any paper that says “water violates all known laws of thermodynamics when you make it a microdroplet” to further their careers
Someone 3y ago
I have my doubts about practical application, too, but the area of 800 km² need not be a show stopper if these things can be stacked, and that seems likely to me. Also, if I understand https://www.pnas.org/action/downloadSupplement?doi=10.1073%2Fpnas.2301206120&file=pnas.2301206120.sapp.pdf https://www.pnas.org/action/downloadSupplement?doi=10.1073%2... correctly, the catalyst weighed 0.22 mg/cm². That’s 2.2g/m² or 2200kg/km² or less than 2 million kg for 800km². So, I guess the amount of catalyst wouldn’t be a problem either, _if_ it is a perfect catalyst that doesn’t degrade and doesn’t require regular cleaning.

usrusr 3y ago

Strong too good to be true vibes. Ammonia is an energy carrier, and in the conventional process that energy comes from H2. Atmospheric nitrogen and water are some of the most inert compounds in existence and that difference has to come from somewhere. Perhaps they just haven't identified the voltage or radiation yet? In a lab setting with an output that extrapolates to 0.005g/m2s, there can be a lot of inputs you just haven't successfully ruled out.

pjc50 3y ago
I'm guessing it's just endothermic, and relies on the energy probability distribution on these droplets to have some atoms of high enough energy to react.
opportune 3y ago
I did a deep dive in seeing how this is even possible, because it shouldn’t be thermodynamically, and it seems like all this “microdroplets allow for seemingly impossible reactions by spontaneously forming peroxide” is actually caused by ozone per some researchers: https://cen.acs.org/research-integrity/reproducibility/Claims-water-turning-hydrogen-peroxide/100/web/2022/05 https://cen.acs.org/research-integrity/reproducibility/Claim... This seems to be an open debate topic in chemistry. But I think it’s basically the case that, everybody knows it has to be ozone because the energy must be coming from somewhere, but knowing it’s ozone makes the dependent studies like this uninteresting (saying “who knows how we seemingly produced ammonia with little power, maybe this will cure climate change” gets your papers a lot more citations and recognition than “there is enough ozone in the air to produce small quantities of peroxide to use in reactions at STP”). Until it’s conclusively debunked people are gonna landgrab any paper that says “water violates all known laws of thermodynamics when you make it a microdroplet” to further their careers

Someone 3y ago

I have my doubts about practical application, too, but the area of 800 km² need not be a show stopper if these things can be stacked, and that seems likely to me. Also, if I understand https://www.pnas.org/action/downloadSupplement?doi=10.1073%2Fpnas.2301206120&file=pnas.2301206120.sapp.pdf https://www.pnas.org/action/downloadSupplement?doi=10.1073%2... correctly, the catalyst weighed 0.22 mg/cm². That’s 2.2g/m² or 2200kg/km² or less than 2 million kg for 800km². So, I guess the amount of catalyst wouldn’t be a problem either, _if_ it is a perfect catalyst that doesn’t degrade and doesn’t require regular cleaning.