Thread: The Ammonia economy NH3, instead of H

The hydrogen economy has a few very difficult barriers in its future. Hydrogen is difficult to transport. It seeps through tanks and storage units, and it has to be kept at an insanely high pressure in order to move useful volumes of it.

So, just to keep from being bored, I was researching energetic chemical combinations that use hydrogen as their main component, and I happened to stumble onto Ammonia, and begin reading about its properties. It looks like a useful competitor for natural gas. It has a fairly high combustion energy, including the ability to do straight-to-electric processes on it. A fuel tank on a car (if we were to go so far as attempting to use it in automobiles) would be about 3 times the size of present fuel tanks, and about 25 ATM pressure, with twice the weight. It can be created using electricity, water, and nitrogen from the air, using the Haber process.

Like most chemical storage mediums, the energy cost to create it is certainly greater than the energy released using it. So, what I'm thinking it could be used for is putting power plants in exotic locations, like if there is a huge river in the backwoods of Canada, and nobody lives near it to benefit from a dam, or some coastal area where the tide is acting on a rocky bluff making a lot of energy. Places where you want to build a power plant, but you know transmission losses will be too severe to get any real use out of it.

The main downside is that it is poisonous (though fortunately it also smells really bad, so people won't breathe it unawares.)

http://www.voxsolaris.com/ammonia.html

http://en.wikipedia.org/wiki/Haber_p..._Haber_process

Oh, sorry that's 8 ATM, not 25.

Also, I should mention that its other advantage over Hydrogen is that it has a high ignition temperature of 651°C and a slow burn speed, so it probably doesn't pose a lot of danger from explosions, compared with the alternatives.

H2 also embrittles metals, but why ship bulk anhydrous ammonia rather than electricity over power lines? 8 atmospheres is much better than 25, but are most of your neighbors really responsible enough to deal with that? Will they have to carry Hazmat suit in car to fill tank?

I agree with you that on paper ammonia looks like a solid option. In reality though (granted, like most alternative energy options) it would be a logistical nightmare to implement. I recently did my thesis on hydrogen storage media and as such I wouldn't count out hydrogen just yet. Before starting the thesis I did a literature review on the major H2 storage media and ironically I concluded that one of the most plausible ones was ammonia.

One promising direction that could be taken in terms of storage is arene chromium tricarbonyls. My research, although incomplete, indicated that H2 could be stored and released on these materials at close to STP using photochemistry. I agree with The Finger Prince in that you want to make any potential storage medium as idiot-proof as possible.

Originally Posted by The Finger Prince

H2 also embrittles metals, but why ship bulk anhydrous ammonia rather than electricity over power lines?

The advantage of a pipeline of NH3 vs. power lines is that power lines have transmission losses, but NH3 would only involve possible losses due to leakage, and the cost of pumping the gas through the pipeline. Over short distances power lines are surely much better, but if you wanted to build a power plant in a very faraway part of the wilderness, like some Mountain river up in Canada, then I think an NH3 pipeline would probably be the better option. Then you can send the energy to wherever you want, anywhere on Earth really, or at least anywhere on the same continent.

8 atmospheres is much better than 25, but are most of your neighbors really responsible enough to deal with that? Will they have to carry Hazmat suit in car to fill tank?

Yeah. That's the big problem with it. People are already skittish enough about nuclear power and other stuff like that. Maybe asking them to brave the dangers of Ammonia would be asking too much?

Originally Posted by Kevvy

One promising direction that could be taken in terms of storage is arene chromium tricarbonyls. My research, although incomplete, indicated that H2 could be stored and released on these materials at close to STP using photochemistry. I agree with The Finger Prince in that you want to make any potential storage medium as idiot-proof as possible.

I tried googling "Arene Chromium Tricarbonyls" after reading your post, but I didn't come up with much. Usually Google is more helpful than that.

Would you consider starting a thread about it? This sounds interesting. Certainly finding a good storage medium would make H2 much more attractive as an option than it is right now.

Originally Posted by kojax

The main downside is that it is poisonous (though fortunately it also smells really bad, so people won't breathe it unawares.)

This is actually rather an understatement. Ammonia is horrendously toxic, and very quickly turns to a deadly poisonous gas. And you are talking vast amounts of it, distributed everywhere. It is inevitable that a major spill would occur in a populated area, sooner or later. It has the potential to kill thousands of people, if a large amount is spilled in the wrong place. I doubt too many will see this as acceptable.

Because ammonia is widely used in industry, refrigeration and agriculture, it has already had many accidents, and a lot of people have been seriously harmed or killed. However, to go to using it as a fuel for personal transport raises the hazard an order of magnitude or more.

Originally Posted by kojax

The advantage of a pipeline of NH3 vs. power lines is that power lines have transmission losses, but NH3 would only involve possible losses due to leakage, and the cost of pumping the gas through the pipeline. Over short distances power lines are surely much better, but if you wanted to build a power plant in a very faraway part of the wilderness, like some Mountain river up in Canada, then I think an NH3 pipeline would probably be the better option. Then you can send the energy to wherever you want, anywhere on Earth really, or at least anywhere on the same continent.

That's why we have high voltage DC power lines in some areas. There isn't the AC magnetic losses, and the high voltage overcomes resistance for the most part.

Pacific DC Intertie

Originally Posted by skeptic

Originally Posted by kojax

The main downside is that it is poisonous (though fortunately it also smells really bad, so people won't breathe it unawares.)

This is actually rather an understatement. Ammonia is horrendously toxic, and very quickly turns to a deadly poisonous gas. And you are talking vast amounts of it, distributed everywhere. It is inevitable that a major spill would occur in a populated area, sooner or later. It has the potential to kill thousands of people, if a large amount is spilled in the wrong place. I doubt too many will see this as acceptable.

Because ammonia is widely used in industry, refrigeration and agriculture, it has already had many accidents, and a lot of people have been seriously harmed or killed. However, to go to using it as a fuel for personal transport raises the hazard an order of magnitude or more.

An understatement indeed.

Almost a certain mass killer should there be a problem.

Yeah. I'm starting to see that it's not viable. Even just using ordinary H2 would be better, despite its difficulties.

It's time to go hunt for a new chemical to put H into. I'm thinking that most of the good, non-toxic candidates will end up having a C in there somewhere, which kind of defeats the purpose. Free carbon isn't exactly as easy to come by as free Nitrogen or Hydrogen.

Originally Posted by kojax

It's time to go hunt for a new chemical to put H into.

Research has already been done on this. If you take biomass, and heat it in the absense of oxygen, it drives off a mixture of volatile organic compounds. If you inject hydrogen gas into this mix, and pass it over a heated catalyst, you end up with a mixture of hydrocarbons. Essentially, you are making petrol from biomass.

Originally Posted by skeptic

Originally Posted by kojax

It's time to go hunt for a new chemical to put H into.

Research has already been done on this. If you take biomass, and heat it in the absense of oxygen, it drives off a mixture of volatile organic compounds. If you inject hydrogen gas into this mix, and pass it over a heated catalyst, you end up with a mixture of hydrocarbons. Essentially, you are making petrol from biomass.

I wonder how difficult a task it would be to uses solar electricity and convert 2(H2O) + CO2 to CH4 + 2(O2)? If we extract the carbon from the air to begin with, we would have no fear of adding to it when we burned it. We already have storage and pipelines in place for natural gas. just add this to the system.

I had to research to see if that was possible. It seems it is, and definitely a better pathway to take than NH3 to be sure. This is great stuff. Sabatier reaction - Wikipedia, the free encyclopedia

Originally Posted by kojax

Yeah. I'm starting to see that it's not viable. Even just using ordinary H2 would be better, despite its difficulties.

It's time to go hunt for a new chemical to put H into. I'm thinking that most of the good, non-toxic candidates will end up having a C in there somewhere, which kind of defeats the purpose. Free carbon isn't exactly as easy to come by as free Nitrogen or Hydrogen.

Ammonia combustion would, it seems to Prince, generate large quantities of NOx and resulting photochemical smog. Still there may be a place for some variation on the theme. Producing explosives using a remote power source would be a natural fit and most chemical explosives use nitrogen compounds. Worth further consideration.

Yeah, this idea is dead. However, the CH4 economy..... that's another story.