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

nature.com

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

#131

Post by jodrellblank »

_aavaa_ wrote: post #86
TheSpiceIsLife wrote: post #46

Earlier quoted context omitted.

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.

The move from cars to SUVs in America was so car manufacturers could skip emissions and safety requirements of cars on the technicality that SUVs are “light truck” chassis[1]. Dan Luu shows that those safety regulations are often a box ticking exercise for manufacturers except Volvo[2]. American stroad design is a particularly bad mix of street and road which is more dangerous for drivers and pedestrians than other designs. And the diesel emissions scandal so many car manufacturers were caught defrauding.

“willingness to trade the safety of people for a cheaper X” is exactly what we should expect car companies (and companies in general) to do, because that’s what they’ve done so often though history.

[1] https://youtube.com/watch?v=jN7mSXMruEo “These stupid trucks are literally killing us” -NotJustBikes

[2] https://danluu.com/car-safety/

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

#132

Post by jojobas »

scythe wrote: post #103
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.

That's for a 1cm^2 electrode, as far as I remember not precious-metal rich either.

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

#133

Post by sidewndr46 »

anon_cow1111 wrote: post #91
sidewndr46 wrote: post #87

Earlier quoted context omitted.

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.

Yes, the difference is tannerite (by yield) is many times more expensive, and much easier to trace when someone buys hundreds of pounds of it from a sporting goods store. Similarly, a random individual buying a half ton of AN would probably trip some kind of alarm bells somewhere.

half ton? If I was headed to a friend's house who owns a farm and they asked me to pick up half a ton of farm supplies I would think nothing of it. Even my truck with its tiny payload can carry that around

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

#134

Post by thfuran »

praveen9920 wrote: post #9
fbdab103 wrote: post #8

Earlier quoted context omitted.

Are there power plants today that burn ammonia directly? If not, is it a simple/cheap enough conversion?

It is actually cheaper because of existing infrastructure that exists for fertilisers manufacturing. But the main concern is that ammonia burns slowly. It might work in power plants but not in EVs

Why would you want to burn ammonia in an electric vehicle?

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

#135

Post by thfuran »

aifooh7Keew6xoo wrote: post #39
adrian_b wrote: post #22

Earlier quoted context omitted.

There has been a lot of research in fuel cells that generate electricity from ammonia, with much simpler storage problems than for hydrogen.

I'm not sure I'd leap to "much simpler storage problems than for hydrogen" for a highly corrosive gas. The lower explosive limit of hydrogen is ~4%. By comparison the 300 ppm immediate danger to life and health threshold of ammonia is .03%. It is intrinsically dangerous, i.e. without a source of ignition, at concentrations 2 orders of magnitude lower than the LEL of hydrogen. Not every hydrogen leak is a concern, but…

But hydrogen likes to make invisible fires and leak through solid steel, and it needs to be ludicrously cold to liquify.

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

#136

Post by thfuran »

jojobas wrote: post #132
scythe wrote: post #103

Earlier quoted context omitted.

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.

That's for a 1cm^2 electrode, as far as I remember not precious-metal rich either.

So you only need an electrode about the size of Monaco to get 1 kg per second. Hopefully you can use some kind of foam or something.

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

#137

Post by greggsy »

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…

Bulk transport, not consumer vehicles

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

#138

Post by NotYourLawyer »

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…

If it uses a laser, it wastes a lot of energy.

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

#139

Post by nullc »

wolfi1 wrote: post #105
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

> (10 to 13 kWh kg−1 NH3) of the H–B process at an industrial scale"

It isn't clear to me how they're pricing the H-B process there, industrial HB uses hydrogen from hydrocarbons. An apples to apples comparison would at least add the energy you could get from burning the hydrogen instead, but arguably should compare with H-B where the hydrogen comes from electrolysis of water.

> "subsequent hydrolysis"

As far as I can tell, you just add water. zap rinse repeat. I'm a little skeptical that their yield figures were for Li2O though the repeated process has you cycling through LiOH after the first pass.

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

#140

Post by pfdietz »

jillesvangurp wrote: post #118
pfdietz wrote: post #11

Earlier quoted context omitted.

Not if the energy efficiency were poor, compared to electrolytic hydrogen into a conventional Haber-Bosch process. And remember hydrogen is very storable, so that process could buffer renewable intermittency and keep the H-B plant running continuously. Electrolyzers are getting cheap.

Actually storing and transporting hydrogen are technical challenges. It takes up a lot of space and hydrogen molecules are so small they leak through a lot of materials. Not impossible but you need a lot of expensive infrastructure to handle it. Most hydrogen produced today is consumed very close to where it is produced. Also energy storage and fuel type use cases rank very low on Michael Liebreich's hydrogen ladder.…

Actually, storage and transportation are positives for hydrogen. It's easier to transport and store hydrogen than it is to transport and store electricity. Hydrogen can be stored underground in caverns very cheaply (this is a demonstrated technology already in use for buffering hydrogen produced from fossil fuels), compared to the cost of equipment for storing electrical energy. Hydrogen is a viable for seasonal storage of renewable energy, unlike batteries.

The negative for hydrogen is poor round trip efficiency of electricity -> hydrogen -> electricity. But for sufficiently long storage times the lower cost of storage capacity vs. batteries overwhelms that, and hydrogen becomes cheaper for grid storage.

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