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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)

#61

Post by gimmeThaBeet »

lazide wrote: post #28
ilyt wrote: post #25

Earlier quoted context omitted.

Well, petrol or diesel isn't that nice either

Anhydrous ammonia is much worse, creating rolling clouds of ground level deadly gas for long distances. And being very flammable. And explosive. Gas doing 2 of those 3, and diesel only 1.

I agree, it's kind of a different class of threat for everyday people.

Not assuming it would be the same, but picturing a spill at a gas station. Spilling gas is a problem, but at least it's just sort of there. If you get an ammonia leak and it forms a vapor cloud, I don't think most people would know how to deal with that. I'll bet your spilled gas likely won't migrate into the intersection.

But on the plus side, we already see what handling/transportation of large amounts looks like for agriculture, even if rail carriers etc. dislike dealing with it.

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

#62

Post by Retric »

aifooh7Keew6xoo wrote: post #51
Retric wrote: post #44

Earlier quoted context omitted.

Anything dangerous at scale has issues. That doesn’t mean people are unwilling to fill up at a gas station or use other hydrocarbon fuels despite plenty of far worse examples. https://www.npr.org/2021/11/06/1053162519/sierra-leone-oil-t... And plenty of more recent examples: https://www.fox29.com/news/tanker-truck-fire-closes-stretch-... Ammonia is one of the most common chemicals manufactured and transported around…

My primary point here is that if you see an ammonia spill you're going to die whether or not it explodes. I suppose it's worth noting in your second link, the fatalities were from the kinetics of the impact, which is a hazard that belongs to "things with velocity" rather than "things containing fuels". We can assume that uncontained fire and explosion are categorical hazards with fuels. Ammonia has significant risks…

Except the risk of fire / explosion is lower. NFPA 704 for gasoline is 1 Health, 3 fire, 0 Instability where Ammonia is 3 Health, 1 fire, 0 Instability

Major spills of either are dangerous but rare compared to how much is being created and transported. We’re only ~5x as much gasoline vs Ammonia today. Considering most cars would be EV’s I suspect the total amount of Ammonia produced even with widespread adoption isn’t going to change by that much. Say Long haul trucks, heavy equipment, aircraft etc.

PS: Which isn’t to say Ammonia is actually a good fuel, the only thing I can think that actually used the stuff was the X-15. So it would need significant economic advantages to end up adopted.

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

#63

Post by jacquesm »

aaronbrethorst wrote: post #57
TheSpiceIsLife wrote: post #46

Earlier quoted context omitted.

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

Neat. I look forward to them rolling out a production model in 2043.

I look forward to them rolling it out downwind.

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

#64

Post by alwayslikethis »

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.…

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, but I'm not an expert in that field, so I can't comment on its merits.

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

#65

Post by rossjudson »

aifooh7Keew6xoo wrote: post #33
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…

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…

Pretty sure they're talking about moving energy, not energy for moving.

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

#66

Post by alwayslikethis »

lazide wrote: post #28
ilyt wrote: post #25

Earlier quoted context omitted.

Well, petrol or diesel isn't that nice either

Anhydrous ammonia is much worse, creating rolling clouds of ground level deadly gas for long distances. And being very flammable. And explosive. Gas doing 2 of those 3, and diesel only 1.

Correction: Ammonia is not flammable since the flash point is significantly above room temperature. It would only be explosive if you consider the pressure vessel exploding, but we also have natural gas powered cars which also have pressurized cylinders. The main real issue is the toxicity.

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

#67

Post by anon_cow1111 »

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.

The issue with hydrogen is that it has a fairly wide combustion range (meaning the ratio of fuel/air that can burn), I can't remember the numbers but it's several times greater than other common fuels. The other issue with hydrogen is that the combustion happens VERY fast... if you ignite gasoline vapor/air in an open 5-gallon jug, you have a nice rocket that'll fly 50 feet or so. If you ignite hydrogen/air in the same jug, you have permanent hearing damage and shards of plastic embedded in you.

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

#68

Post by Taiwan_No_1 »

anon_cow1111 wrote: post #67
sfink wrote: post #53

Earlier quoted context omitted.

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.

The issue with hydrogen is that it has a fairly wide combustion range (meaning the ratio of fuel/air that can burn), I can't remember the numbers but it's several times greater than other common fuels. The other issue with hydrogen is that the combustion happens VERY fast... if you ignite gasoline vapor/air in an open 5-gallon jug, you have a nice rocket that'll fly 50 feet or so. If you ignite hydrogen/air in the sa…

[dead]

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

#70

Post by CuriousCosmic »

im3w1l wrote: post #60
lazide wrote: post #28

Earlier quoted context omitted.

Anhydrous ammonia is much worse, creating rolling clouds of ground level deadly gas for long distances. And being very flammable. And explosive. Gas doing 2 of those 3, and diesel only 1.

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 temperature and non-reactive... until it comes into contact with water at which point it all turns back into hydrazine.

But yeah no there's really not a "nicer" fuel. Generally, if it has nitrogen in it and it isn't literally just nitrogen with itself, it's dangerous. And the more nitrogens it has the more dangerous it is.

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