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Biotech Science

Chemists Discover New Way To Harness Energy From Ammonia (phys.org) 119

fahrbot-bot shares a report from Phys.Org: A research team at the University of Wisconsin-Madison has identified a new way to convert ammonia to nitrogen gas through a process that could be a step toward ammonia replacing carbon-based fuels. The discovery of this technique, which uses a metal catalyst and releases -- rather than requires -- energy, was reported Nov. 8 in Nature Chemistry and has received a provisional patent from the Wisconsin Alumni Research Foundation.

The scientists were excited to find that the addition of ammonia to a metal catalyst containing the platinum-like element ruthenium spontaneously produced nitrogen, which means that no added energy was required. Instead, this process can be harnessed to produce electricity, with protons and nitrogen gas as byproducts. In addition, the metal complex can be recycled through exposure to oxygen and used repeatedly, all a much cleaner process than using carbon-based fuels. "We figured out that, not only are we making nitrogen, we are making it under conditions that are completely unprecedented," says Berry, who is the Lester McNall Professor of Chemistry and focuses his research efforts on transition metal chemistry. "To be able to complete the ammonia-to-nitrogen reaction under ambient conditions -- and get energy -- is a pretty big deal."

Ammonia has been burned as a fuel source for many years. During World War II, it was used in automobiles, and scientists today are considering ways to burn it in engines as a replacement for gasoline, particularly in the maritime industry. However, burning ammonia releases toxic nitrogen oxide gases. The new reaction avoids those toxic byproducts. If the reaction were housed in a fuel cell where ammonia and ruthenium react at an electrode surface, it could cleanly produce electricity without the need for a catalytic converter.

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Chemists Discover New Way To Harness Energy From Ammonia

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  • If I get this right, the only real input is one thing we literally need every minute.

    However, we plant trees to make oxygen from carbon dioxide. Might actually work out well. How soon until the plant scale?

    • Every gas, diesel and jet engine burns oxygen.
    • Couldn't we just plant trees inside cars and trucks instead?

    • by gweihir ( 88907 )

      Somebody did sleep in Chemistry class.

      Yes, almost everything that can be used as an energy source via chemical reaction consumes Oxygen. However we do _not_ have any kind of Oxygen shortage on this planet. There is plenty and it is not in any danger of running out.

      • > However we do _not_ have any kind of Oxygen shortage on this planet. There is plenty and it is not in any danger of running out.

        Cite .. required, last I looked we are burning down the house.
        • by gweihir ( 88907 )

          > However we do _not_ have any kind of Oxygen shortage on this planet. There is plenty and it is not in any danger of running out.
          Cite .. required, last I looked we are burning down the house.

          No. Claiming we are running out of oxygen is an extraordinary claim. You are required to provide extraordinary proof to have it even considered.

          What is happening is that we have global warming from too much greenhouse gasses. That is something else entirely.

  • by Baron_Yam ( 643147 ) on Saturday November 13, 2021 @10:24AM (#61984097)

    Ammonia is potentially great as a renewable resource - but humans churn out about 2g a day of ammonia.

    You can also get ammonia from decomposing organics, so I guess landfills become more important. I don't see us capturing ammonia from farm animals. And you should be able to generate ammonia industrially from bacteria.

    And the energy density issue - ammonia has about half the energy density of gasoline - isn't much of an issue as it's still far better than the best electric car battery by a factor 50.

    Add in that this process would run via a fuel cell to produce electricity, and what you really have is a 'battery pack' to plug in to electric cars that instantly and vastly increases their range... and allows for 'charging' the same way you currently pump gasoline.

    All that without the environmental issues of a high density battery pack. I say 'start up the ammonia bioreactors'.

    • by Crashmarik ( 635988 ) on Saturday November 13, 2021 @10:46AM (#61984141)

      I know sanity is gone from the world but Ammonia is one of the largest manufactured chemical products in the world today, and the Haber Bosch process is not a net producer of energy.

      https://www.aiche.org/resource... [aiche.org]

      Unless you have a way to make Ammonia that doesn't involve consuming energy this is just another alternate type of battery.

      • by gweihir ( 88907 )

        Unless you have a way to make Ammonia that doesn't involve consuming energy this is just another alternate type of battery.

        Yes, so? Is improving battery tech, in particular at those storage densities for mobile use a worthwhile goal?

      • this is just another alternate type of battery.

        Which is something we REALLY need. We badly need a sustainable way to store and transport energy. From daytime to night, and from Australia to Japan and other places that can't produce for themselves. Just one chemical process that can produce some gas or liquid for trade around the globe.

        • Explaining is a pain, usually you are talking to someone who is ignorant and is just seeking validation

          It's even worse when you are talking to someone who is triggered and isn't accepting input or even looking for input.

          Ruthenium spot price $610/oz
          Ruthenium availability in the crust 78th three steps behind gold at 75 estimated amount 1/3rd to 90% that of gold

          Not going to see ruthenium ammonia batteries competing any time soon.

          • It really depends on how much Ruthenium is required to make a good fuel cell. You mention gold: we routinely plate the pads and contact points on circuit boards (as well as other electrical connectors/contacts) with gold, and those things are mass produced.
          • Palladium is spot priced at around $1000/oz, and we mass produce catalytic converters with several grams of it and related metals. So it totally depends on how much is needed.
      • by Roger W Moore ( 538166 ) on Saturday November 13, 2021 @12:31PM (#61984319) Journal
        The Haber-bosch process also produces lots of CO2 so not only does it take energy, but it also produces the one gas we really want to avoid. If the intent is to power vehicles from ammonia produced this way it will be much worse than a battery.
      • The idea is to make ammonia from dihydrogen produced by electrolysis of water when renewables produce excess electricity.

        Bot how do they use the Haber Bosh process in a green fashion ? I don't know.

      • "Unless you have a way to make Ammonia that doesn't involve consuming energy this is just another alternate type of battery."

        That's any fuel. You are against any fuel. Why do you hate fuels?

        Since any fuel production is a net consumer of energy, because it's in the fuel, the value of the fuel is how good is it at storing, transporting, and transforming energy versus other fuels. If you are driving the process with energy that is otherwise too hard to store, transport, and transform, you compare the energy yo

        • That's any fuel. You are against any fuel. Why do you hate fuels?

          Up your trolling skills.

          Almost all fossil fuels are net energy positive
          Alcohol and biofuels are net energy positive
          Nuclear fuels are all net energy positive.
          Hydrogen produced from solar is net energy positive.

          • Almost all fossil fuels are net energy positive

            Not true at all. It's just the costs were paid millions of years ago before we even evolved.

            It still took energy to generate fossil fuels - they're a carbon battery holding ancient solar power for us.

            • Almost all fossil fuels are net energy positive

              Not true at all. It's just the costs were paid millions of years ago before we even evolved.

              It still took energy to generate fossil fuels - they're a carbon battery holding ancient solar power for us.

              Why stop there?

              Every conceivable fuel is just a reservoir for energy released in the big bang.

              • The reason I stop there is because it's a practical place to stop.

                Fossil fuels are increasing in price because we've burned through the easy to reach stuff... the energy required to create more is actually a significant factor to consider.

                In theory we can capture atmospheric CO2 and create synthetic fuels with the injection of some energy, presumably from renewable resources.

                • The reason I stop there is because it's a practical place to stop.

                  Fossil fuels are increasing in price because we've burned through the easy to reach stuff... the energy required to create more is actually a significant factor to consider.

                  In theory we can capture atmospheric CO2 and create synthetic fuels with the injection of some energy, presumably from renewable resources.

                  You stop there because it's practical ?

                  Hmmm I suppose it's impractical to consider that synthesizing Ammonia is a lossy energy conversion process
                  That once it's synthesized distributing it as a fuel is another lossy process
                  Converting it back into electricity is also a lossy process.

                  Even if the the recovery rate for charge in a hypothetical Ammonia battery is as good as current batteries
                  The overall system is considerably worse.

                  Glad you considered this and made your determination of what parts of the system we

            • Oh and in case you didn't understand comments like yours are why I dislike explaining to stupid and willfully ignorant people

              Have a nice day

      • Just like pure hydrogen, ammonia is a medium for the storage of energy (actually hydrogen). It’s much more convenient to store than pure hydrogen. The question are how densely it store energy (ie hydrogen) per kg and lt, and how efficient are the processes for getting to and from ammonia. It sounds like this is a more efficient way to split out the nitrogen and hydrogen (though the extract doesn’t actually mention hydrogen at any point, which is weird as there’s three times as much hydroge

        • Pardon me but no
          The question is how efficient is synthesizing Ammonia and distributing and converting it back to electricity or using it directly as a fuel as part of the overall system?

          Seeing as you have renewables fall off production for months

          https://www.ft.com/content/0a9... [ft.com]

          As The UK found out with offshore wind
          You need to ask can that overall system generate months worth of surplus and cover for the shortfalls.
          Hate to have that happen in the winter when solar is also only providing minimal power.

    • by HiThere ( 15173 )

      The question to my mind is "How common is Ruthenium?". https://en.wikipedia.org/wiki/... [wikipedia.org] reports that is is usually found as a minor component of platinum ores, so I'd guess it's pretty rare. That would mean that any increase in use would really drive up the price, so this may not be practical for any widespread use.

      • It really depends on how much Ruthenium is required to make a good fuel cell. The catalyst probably needs high surface area only, so not necessarily a large mass of Ruthenium.
        • by HiThere ( 15173 )

          IIUC it wouldn't be a massive use, but when only extremely small quantities are available, ANY use will drive up prices (unless that cause better sources to be developed). Look at what's happened with Lithium. It's not strictly comparable, since a lot more Lithium is used per battery, but there also appears to be a lot more of it around.

    • Comment removed based on user account deletion
  • All over the world many fertilizer plants perform the opposite chemical reaction - converting nitrogen to ammonia. Because to plants, molecular nitrogen is pretty much useless, with some exceptions, like beans. So, I have reasons to doubt the practical value of this research.

    • by HiThere ( 15173 )

      That's a reason it's not a good *source* of energy. It could still be a good battery, though I have my doubts.

    • by gweihir ( 88907 )

      This is about fossile fuel replacement due to energy density. It is not about original energy generation. Quite obviously.

  • by hfbaker ( 2602077 ) on Saturday November 13, 2021 @10:42AM (#61984131)
    The production of ammonia released 451 million tons of CO2 in 2010. Each mole of ammonia gas produces one mole of CO2.
  • Hold on a sec... (Score:5, Informative)

    by ixneme ( 1838374 ) on Saturday November 13, 2021 @10:44AM (#61984135)
    I was under the misguided impression that the Fitz-Haber method of generating ammonia from elemental nitrogen and large amounts of energy and pressure was actually a very useful discovery that spared us from scraping cave walls for saltpetre or harvesting bat guano. How exactly does the reverse help us?
  • Further info (Score:5, Informative)

    by jenningsthecat ( 1525947 ) on Saturday November 13, 2021 @10:46AM (#61984143)

    TFA has a link at the end that provides related information:
    https://phys.org/news/2021-10-photocatalyst-ammonia-atmospheric-nitrogen-room.html

    That page in turn has another worthwhile link:
    https://phys.org/news/2021-08-alchemy-carbon-neutrality-ammonia-renewable.html

    Geez, I really need to RTFA more often!

  • I'm too lazy to RTFA. Hello 6 me out.
    NH4 --> N2 + stuff happens continuously everywhere.

    How much energy does this catalytic process create? Hour much of that energy can do work (in the sense of force times distance)?

    Also, converting NH4 to N2 faster would really help me keep my aquarium healthy. Can I just throw in some catalyst and watch the nitrate levels in my fish tank go down?

  • Where are they getting the ammonia? The usual source these days is synthetic from nitrogen and water with a catalyst -- the exact opposite of the process they are discussing The Haber-Bosch process for producing it for fertilizer, developed in Germany when they were cut off from supplies of natural fertilizer by WW1. It requires a large input of energy -- the same energy you are getting out by burning it. Also burning ammonia produces nitrogen oxides which are major pollutants as well as nitrogen gas.
    • by dryeo ( 100693 )

      Think of it more as a battery. Solar cells produce ammonia during the day and ammonia turned to electricity during the night kind of thing. A lot easier to transport as well.
      And they're producing electricity from the reaction, not burning it so the waste is nitrogen and hydrogen. I'd assume the hydrogen is diluted enough to not be a hazard.

  • by eric_harris_76 ( 861235 ) on Saturday November 13, 2021 @01:01PM (#61984383)
    If you see a modified Delorean with no Mr. Fusion, but it does have a Mr. Catalyst, you'll know not to feed it beer cans and banana peels. Instead, just pee into the fuel tank.
  • releases toxic nitrogen oxide gases

    Not plant food!

  • Could be a niche spacecraft propellant, in a domain with a rich ammonia source but not much free oxygen. You get a gas and electricity to ionize it so it can push your thing around in space.
  • Oil companies are behind all kinds of "green" fuels like this and hydrogen. It's more efficient to just burn the natural gas directly.

  • I see no advantages of this over a hydrogen fuel cell. Ammonia is gas just like hydrogen and would have to be stored under pressure. In addition, unlike hydrogen it is toxic and corrosive. This looks like someone plugging their research rather than a real solution to anything.
    • Under pressure ammonia liquefies. The stored energy density of ammonia is *much* higher than hydrogen. It behaves more like propane than hydrogen.

      Hydrogen is also the 'leakiest' gas, because of the extremely small size of the molecules.

  • From TFA:

    "We have an established infrastructure for distribution of ammonia, which is already mass produced from nitrogen and hydrogen in the Haber-Bosch process," says Michael Trenerry, a graduate student and author on the paper. "This technology could enable a carbon-free fuel economy, but it's one half of the puzzle. One of the drawbacks of ammonia synthesis is that the hydrogen we use to make ammonia comes from natural gas and fossil fuels."

    This trend is changing, however, as ammonia producers attempt to produce "green" ammonia, in which the hydrogen atoms are supplied by carbon-neutral water electrolysis instead of the energy-intensive Haber-Bosch process.

    Uh, this is a big issue. Ammonia doesn't occur in nature in any great quantities. It takes energy to create it, either with Haber-Bosch [wikipedia.org] or green methods and it takes more energy than you get out by reacting it in a fuel cell. Breezily saying we'll go green is kind of like saying a honey badger is a great pet, all we have to do is breed them to be less vicious. This is the same problem which keeps us from using hydrogen as a fuel, it takes too much energy to create the fuel in the first place.

    Let's

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