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Nitrogen electroreduction with almost 100% current-to-ammonia efficiency (2022)

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Re: Nitrogen electroreduction with almost 100% current-to-ammonia efficiency (2022)

#101

Post by nukeman »

nick222226 wrote: post #98
amluto wrote: post #82

Earlier quoted context omitted.

There were some recent articles suggesting that there may be enough natural hydrogen seeping out of the ground to supply all of humanity’s energy needs. It seems a bit unlikely that leakage of hydrogen from fuel systems would matter much in comparison.

How about radon, is that fissible?

No, it gives off alpha particles and gamma rays. Hypothetically, you could build a device to harvest that energy (along the lines of an RTG), but the energy density and conversion efficiency would be laughable, given the 3.8 day half-life and gaseous state.

Re: Nitrogen electroreduction with almost 100% current-to-ammonia efficiency (2022)

#102

Post by anon_cow1111 »

lazide wrote: post #97
anon_cow1111 wrote: post #93

Earlier quoted context omitted.

Well of course, but that only works once before you get traced and caught, might still be acceptable for the aforementioned crazy guy but I assume most others would rather blend in with the 50 million people buying gas on any given day.

Anhydrous ammonia is even more illegal in most places to get - apparently it’s a precursor to meth production or something?

I heard something about this too, though I omitted it for the sake of brevity. Don't know the specifics, but yes I think it's also a drug precursor. I remember some CCTV footage of people stealing ammonia from large tanks on a farm, not sure what other reason they would have other than drug production.

Re: Nitrogen electroreduction with almost 100% current-to-ammonia efficiency (2022)

#103

Post by scythe »

londons_explore wrote: post #2

Big if true... This could enable fertilizer production with no CO2 emissions. The numbers in the paper suggest that it might prove cheaper than natural gas based production which is common today. Fertilizer production is 2.1% of all CO2 emissions right now.

Oh it's true. But as the paper states, they produced 3.9 millimoles — 0.068 grams — of ammonia in 96 hours.

So I'm not exactly holding my breath. It's a big improvement over previous methods, but there's still a long way to go.

Re: Nitrogen electroreduction with almost 100% current-to-ammonia efficiency (2022)

#104

Post by idontwantthis »

PumpkinSpice wrote: post #38
aifooh7Keew6xoo wrote: post #33

Earlier quoted context omitted.

Where are all the people that complain about the dangers and impracticality of hydrogen when the topic of using a corrosive gas that poses an immediate danger to life and health at concentrations as low as 300 ppm as a fuel comes up? They're trying to avoid using the stuff in industrial refrigeration it's so nasty, and yet here we are gleefully considering rolling down the highway with it in the cheapest vessel indus…

I don't think it's realistic as a fuel for cars, but "worldwide transportation" means more than that. I suspect they're talking about container ships, tankers, and such. Ammonia is easier to liquify than hydrogen, and is in many respects easier to handle. However, it's definitely not something you want to have a spill of at a gas station or in your garage, and for that reason, it probably won't have "consumer" uses.…

I wonder if this process would be easy enough that “ammonia battery” plants would just synthesize on site when solar power is high. Like charging up a battery with no need to move anything.

Or maybe a regional factory with short pipelines.

Re: Nitrogen electroreduction with almost 100% current-to-ammonia efficiency (2022)

#105

Post by wolfi1 »

zeristor wrote: post #27

Looking at the paper, in similar papers reference is made to this paper published 13th September 2023: “Laser-induced nitrogen fixation” https://www.nature.com/articles/s41467-023-41441-0 This is Open Access, and mentions how that is also a leap forward in Nitrogen fixation “Abstract: For decarbonization of ammonia production in industry, alternative methods by exploiting renewable energy sources have recently been e…

"The corresponding lowest energy consumption of ammonia synthesis based on the light power can be calculated to be approximately 322 kWh kg−1 NH3 (Fig. 3b). This value is significantly higher than that (10 to 13 kWh kg−1 NH3) of the H–B process at an industrial scale" still way to go. found nothing about the "subsequent hydrolysis" step, skimming the article

Re: Nitrogen electroreduction with almost 100% current-to-ammonia efficiency (2022)

#106

Post by snewman »

HPsquared wrote: post #3

What does the term "current-to-ammonia efficiency" mean here? I imagine it would refer to the specificity of the reaction, i.e. that 99% of the electrons passing through the system are used in the main reaction, and The abstract doesn't go into detail on energy efficiency and a comparison to the old method using gas. For instance, would this method result in less CO2 emissions using regular grid electricity, or would…

Bear in mind that grid electricity is getting cleaner over time. We need to skate to where the puck is going, which is 100% clean electricity. Now is an excellent time to be developing and preparing to scale technologies that work well with clean electricity.

Re: Nitrogen electroreduction with almost 100% current-to-ammonia efficiency (2022)

#107

Post by ororroro »

Superfluidity wrote: post #20
credit_guy wrote: post #6

Earlier quoted context omitted.

The scalable part is going to be difficult though. This is not all that different from the production of hydrogen. Hydrogen is most economically produced from natural gas nowadays. You can produce it from water, with (just like here) an almost 100% current-to-hydrogen efficiency. But it's still twice as expensive, if not more.

Electrolysis of water is 70–80% efficient (a 20–30% conversion loss) while steam reforming of natural gas has a thermal efficiency between 70 and 85%. https://en.m.wikipedia.org/wiki/Hydrogen_production#:~:text=... .

Current/Faraday efficiency is an entirely different thing. 100% current efficiency means you won't get a buildup of side products or erosion of your electrodes due to stray electrons. In isolation it is not a measure of power efficiency.

Re: Nitrogen electroreduction with almost 100% current-to-ammonia efficiency (2022)

#108

Post by jandrewrogers »

anon_cow1111 wrote: post #84

I need to ask this question for any chemical engineers currently reading this. I'm seeing people in the comments talking about how this could be applied to consumer vehicles, not just industry like cargo ships and agriculture. If I, the consumer, had unlimited access to cheap, unregulated liquid ammonia (as common as gasoline), how many precursor-steps am I away from having access to like... a LOT of high explosives?…

Synthesizing high explosives from anhydrous ammonia is not trivial and no random person would ever bother. There are easier precursors to work with and much easier ways to acquire high explosives than trying to bootstrap from ammonia.

And if someone really was bent on mayhem, well, anhydrous ammonia is nasty toxic stuff as is. You don’t need to do anything chemically to it to kill or injure a lot of people. On the other hand, it isn’t a chemical that sneaks up on you. If you are being exposed to dangerous levels, you’ll know it.

Re: Nitrogen electroreduction with almost 100% current-to-ammonia efficiency (2022)

#109

Post by eternauta3k »

jtbayly wrote: post #13
RetroTechie wrote: post #7

Earlier quoted context omitted.

Not just fertilizer: "In addition to its use in the fertilizer and chemical industries, ammonia is currently seen as a potential replacement for carbon-based fuels and as a carrier for worldwide transportation of renewable energy." Long-term grid storage? Publication: 22 July 2022 Anyone know if maybe some pilot / small scale production facility has been set up in the mean time? I've read about a farm that produced i…

Farms have been producing their own fertilizer for centuries. ;-)

Yes, and yields were crap back then. Guano and then synthetic fertilizer changed everything.

Re: Nitrogen electroreduction with almost 100% current-to-ammonia efficiency (2022)

#110

Post by eternauta3k »

From https://en.wikipedia.org/wiki/Haber_process#Process:

> ammonia production is energy-intensive, accounting for 1% to 2% of global energy consumption, 3% of global carbon emissions,[23] and 3% to 5% of natural gas consumption

Big if we can improve this.

For more on the Haber process and its impact on the world, I highly recommend this book: "The Alchemy of Air: A Jewish Genius, a Doomed Tycoon, and the Scientific Discovery That Fed the World but Fueled the Rise of Hitler" by Thomas Hager.

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