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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)

#81

Post by lazide »

CuriousCosmic wrote: post #70
im3w1l wrote: post #60

Earlier quoted context omitted.

Could we use this process as a building block in the synthesis of some "nicer" fuel? What can ammonia be semi-efficiently converted to? Edit: Maybe methanol?

Well... there's hydrazine (N2H4) which is the stuff they use as monopropellant rocket fuel. It burns even without the presence of oxygen and it's even more toxic and explosive than ammonia. It's the reason the capture crews for returning spacecrafts wear hazmat suits. However hydrazine is liquid at room temperature and it can be converted to hydrazone (also being considered for fuel cells) which is solid at room temp…

If there is anything that would make ammonia seem warm and cuddly, it is indeed hydrazine!

Urea maybe? It’s almost non toxic and is 2x ammonia + a carbon monoxide molecule.

though not sure how efficient it would be to extract energy from.

Speaking of ‘extra nitrogen’s are generally bad’, a callout to the azides!

https://en.m.wikipedia.org/wiki/Azide

https://en.m.wikipedia.org/wiki/Lead(II)_azide

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

#82

Post by amluto »

alwayslikethis wrote: post #64
PumpkinSpice wrote: post #38

Earlier quoted context omitted.

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.…

It is important to note that hydrogen, due to the small size of the molecule, is really hard to contain as a gas. Moreover, leaked hydrogen gas is an indirect but potent greenhouse gas via interfering with the degradation of existing methane in the atmosphere. If we leak enough hydrogen, we might not be helping the climate very much. I was once in a presentation which claimed formic acid to be a better alternative, b…

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.

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

#83

Post by [deleted] »

RetroTechie wrote: post #7
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.

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…

[deleted]

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

#84

Post by anon_cow1111 »

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?

-asking for your friendly neighborhood crazy person with a vendetta against... whoever.

As far as I can see, it's a very similar problem to hydrogen. It doesn't matter how safe you can make it, it matters how dangerous a random nutjob can make it.

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

#85

Post by Paul-Craft »

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.

Not until you can generate electricity at grid scale without CO2 emissions. That includes building the infrastructure to do so. Even nuclear doesn't get you there.

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

#86

Post by _aavaa_ »

TheSpiceIsLife wrote: post #46
PumpkinSpice wrote: post #38

Earlier quoted context omitted.

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.…

Toyota have produced a prototype ammonia engine they claim is the end of the EV market.

They can keep making claims to cover up their complete bungling of their market position.

As for the idea itself. Ammonia as fuel fails the first principle of safe design. It’s a poisonous gas. Using it as a fuel is a willingness to trade the safety of people for a cheaper fuel.

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

#87

Post by sidewndr46 »

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?…

What would it matter? I can go buy as much materials to make explosives as I want today.

Or I could just purchase actual explosives at the sporting good store, like tannerite.

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

#88

Post by seventytwo »

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?…

It only needs to be as safe as fossil fuels, or even slightly less safe, if the benefits are higher.

This always bothers me. People freak out about LiIon battery failures, or hydrogen, or ammonia, or nuclear power. But here we are with an entire economy riding on an explosive, firey, dirty fuel that is already causing global climate problems.

Safety concerns should be kept on-par with what we have today. Let’s not throw out a good solution because it can be dangerous in some cases. Any high-energy-dense thing we switch to after fossil fuels is going to release that energy if handled improperly. That concern should be quite low on the list.

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

#89

Post by amluto »

sfink wrote: post #53
justinclift wrote: post #45

Earlier quoted context omitted.

Hmmm, "gas station filled with petrol that explodes" vs "gas station filled with hydrogen that explodes". Being near either one as it explodes would be bad, but I wonder which one looks more impressive movie-effects-wise? :)

In my limited understanding, neither one really explodes. The petrol one would look like a huge impressive fireball that launches a big black mushroom cloud and then just burns like crazy. The hydrogen one, if the hydrogen is fairly pure, would be like a big faint blue wispy fireball, not all that impressive. If there were an oxidizer in the mix somehow, it would be rather more explosive.

If the hydrogen is fairly pure and the amount is question is small, then sure: combustion will happen at the hydrogen-air interface. If it mixes with air before ignition, then it can burn all a once, and Wikipedia informs me that “the limits of detonability of hydrogen in air are 18.3% to 59% by volume.”. Yes, it will literally detonate with supersonic flame velocity.

I once got to watch some moderately crazy students fill an ordinary party balloon with a stoichiometric mix of hydrogen and oxygen at ambient temperature and pressure. When it was ignited, the result was extremely impressive. No one was injured (because we were all warned to protect our ears and open our mouths and balloons don’t produce significant shrapnel), but the shock wave was not at all subtle.

https://en.m.wikipedia.org/wiki/Hydrogen_safety

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

#90

Post by vGPU »

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?…

You can buy ammonium nitrate in bulk. Much easier to turn into an explosive if that’s the point you’re making. Just say you’re opening a farm and off you go.
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