Talk:Ammonia

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Former good article nominee Ammonia was a Natural sciences good articles nominee, but did not meet the good article criteria at the time. There are suggestions below for improving the article. Once these issues have been addressed, the article can be renominated. Editors may also seek a reassessment of the decision if they believe there was a mistake.

Peacock and Disputed templates on Fuel section[edit]

I added these templates because the section about use as a fuel has a large amount of information which seems both biased and questionable- it seems like it was written by a promoted for NH3 as a fuel for automobiles and the information provided doesn't really add up- the section about storing NH3 in existing fuel tanks, pressurizing a vessel that was not designed to be pressurized, is especially dubious. This doesn't belong in an encyclopedia. 63.243.13.194 (talk) 22:04, 29 October 2015 (UTC)

production costs[edit]

Can anyone give the relative current production costs of say liquid ammonia and say diesel, along with a comparative calorific value?

energy efficiency of making ammonia from renewable electricity compared to using battery technology[edit]

Hi can anyone comment or provide answers?.....copy of letter sent to Hydro

.....................................Engineman (talk) 05:37, 9 June 2008 (UTC)


Hello,

I am writing a chapter to go in a book on renewable energy, and one of my potential topics is the use of ammonia as a liquid fuel for vehicles - this has been suggested as an alternative energy carrier if made by electrolysis of water from renewable energy sources and is on the fact of it, a much better carrier than say hydrogen.

The key question is, what is the net efficiency with with which hydrogen can be produced by electrolysis.

I understand that only 70% of the energy is transferred to the hydrogen (for subsequent reaction into ammonia.) if burnt in a car engine at 40% efficiency, therefore the overall efficiency is only 28%, whereas a battery can achieve 70% round trip efficiency.

However, if the waste heat from the electrolysis is at sufficiently high temperature, this heat can be used in say District Heating applications, which improves the overall energy balance significantly ie is an energy offsett.

Furthermore, as I understand it, oxygen will be liberated in the electrolysis production process and presumably this can replace oxygen made by other energy intensive means again given an energy offset.

Can you therefore provide me with any relevant information on the net energy requirement for producing hydrogen by electrolysis?

I enclose an extract from a wikipedia article which I have contributed which outlines my thinking further.

Kind Regards

Engineman Claverton Energy Group


[edit] Fuel Ammonia was used during World War II fuel shortages to power buses in Belgium and used in engine and solar energy applications prior to 1900. Liquid ammonia was used as the fuel of the rocket airplane, the X-15. Although not as powerful as other fuels, it left no soot in the reusable rocket engine and its density approximately matches that for the oxidizer, liquid oxygen, which simplified the aircraft's design.

I do not understand the statement about the density being equal to liquid oxygen (LOX) simplifying the aircraft's design. Liquid Ammonia has a density of about 671 kg/m^3 while liquid oxygen is about 1,140 kg/m^3. The XLR-99 ran at a mixture ratio of 1.25 (MLOX/MNH3). This would indicate that the required tank volumes are not equial; the volume of the LOX required is about 73% of the ammona volume. Ammona density - http://www.airgasspecialtyproducts.com/Libraries/Technical_Bulletins/Temperature_-_Density_Chart_for_Liquid_Anhydrous_Ammonia.sflb.ashx LOX density - en.wikipedia.org/wiki/Liquid_oxygen XLR-99 data - History Of Liquid Propellant Rocket Engines, George P. Sutton, 2006 AIAA, pg. 314 Jedswift (talk) 15:49, 18 April 2013 (UTC)

Ammonia is proposed as a practical, clean (CO2-free), alternative to fossil fuel for internal combustion engines.[20] In 1981 a Canadian company converted a 1981 Chevrolet Impala to operate using ammonia as fuel.[21][22] Ammonia is marketed as a low-emission fuel.[23]

According to Google, Ammonia is running at about $500/tonne. This compares with the present crude oil price at $120 barrel, which is equivalent to about $850 tonne.

The calorific value of ammonia is 22.5 MJ/kg which is about half that of diesel. In addition because of the high hydrogen content of ammonia, in a normal engine, in which the mositure is not condensed, the calorific value of ammonia will be about 20% less than this figure.

Ammonia is comparable to gasoline as a fuel for combustion engines. Three gallons of ammonia is equivalent to one gallon of gasoline in energy content. In other terms, 2.35 pounds of ammonia is equivalent to one pound of gasoline in energy content. Cost wise in 1998, bulk ammonia was $1.13 per gallon gasoline equivalent.

This section of the article as it stands is inconsistent: if it takes 2.35lbs of ammonia to replace the energy equivalent of 1lb of gas, then it takes 2.35 tons to replace 1 ton of gas; at $500/ton, that's $1,175, way more expensive than gas at $850. One or both of these "facts" (my italics) is therefore wrong.--DLuber1 (talk) 21:05, 11 June 2008 (UTC)

[edit] Use as a diesel / gasoline / petrol replacement The potential attractions are large:

Upside

Its here now, available in large quantities.

It can apparently be burnt in modern high speed car engines with little modification, other than the addition of 5% pilot fuel - which could be hydrocarbon or hydrogen, of which the latter could be stored on board. [24]

It is compressible / liquefiable / dense enough to fit into existing cars. It would get all the "Jeremy Clarkson" benefits of manly, noisy piston engines compared to the non manly whine of a motor.

There would be less opposition from the motor trade who want to carry on the lucrative business of expensive to maintain IC engines.

At the moment the ammonia price is about the same or less per unit energy than petrol albeit it this is based on natural gas feedstock.

Same problem as above. It can logically never cost less per unit energy than natural gas if the ammonia is produced by partial oxidation of natural gas in the Haber process. --DLuber1 (talk) 21:05, 11 June 2008 (UTC)

No greenhouse emissions

Less toxic and flammable etc.

Huge manufacturing infrastructure exists based on natural gas, but only the front end of the process needs to change.

Huge ammonia distribution infrastructure already existing

Could be produced using electricity from renewable and fluctuating wind power.

Could be produced from remote renewable energy sources in the middle of say the Gobi desert / Sahara wind / and shipped to markets.

Ian readily be used in modern engines since unlike methanol it will not damage seals and pumps.

battery powered cars will require some form of stored fuel to heat the occupants in winter whereas as ammonia means drivers could carry on using the existing engine waste heat method.


Downside:

The efficiency will be less than a battery powered car at 70%. It seems that ammonia can be burnt at around 40% [25]

hydrogen can be electrolysed at say 70% efficiency and burnt in a car at around 40% [26] given 28% overall, which is half that of a battery.


However, if the 30% waste heat can be used in say district heating this ups the effective efficiency.

Also the electrolysis of water not only gives hydrogen, but also oxygen - this is normally produced at huge energy cost from the air using electricity - so presumably there are offset energy efficiencies there.

Clearly the energy balance for producing ammonia from electricity, and the offset oxygen production cost, use of waste heat offset energy cost, and at what temperature the waste heat is available at are crucial.

Any one got any other comments / references.

Apparently it was used to run buses in Belgium in WW2[27]

Potential production from renewable energy sources:

The 60 MW hydro station at Vermork, Norway provided most of Europe's ammonia fertilizer, from 1911 onwards to the '30s, by electrolysis of water, to hydrogen, and then synthesis from hydrogen plus air to ammonia. So "green" ammonia could be produced in a similar fashion from renewable energy generation schemes.





Pure ammonia is not suitable for use in high-speed engines. Its flame speed is too low.

However, ammonia can be doped by environmentally friendly chemical additives, and thus be compatible in high-speed engines. [28]


The efficiency in an IC engines is around 50%, but that is probably LCV so HCV efficiency may be nearer 40%....[29]


Ammonia is comparable to gasoline as a fuel for combustion engines. Three gallons of ammonia

is equivalent to one gallon of gasoline in energy content. In other terms, 2.35 pounds of

ammonia is equivalent to one pound of gasoline in energy content. Cost wise in 1998, bulk

ammonia was $1.13 per gallon gasoline equivalent.[30]


If the Hydrogen Engine Center ammonia fueled commercial internal combustion engines are as high in efficiency (50%) as Ted Hollinger indicates, it will be difficult for fuel cells to compete," commented Norm Olsen, P.E., Manager of Iowa State University's BECON (Biomass Energy Conversion) Facility in Nevada, IA. [31]



Ammonia fuel: the key to hydrogen-based transportation MacKenzie, J.J. Avery, W.H. World Resources Inst., Washington, DC;

Ammonia (NH3) is a high octane fuel (110) that can replace CO2 producing fuels in automobile transportation. It shares with hydrogen the virtue of yielding only water and nitrogen as combustion products when burned in internal combustion engines but avoids the packaging, safety and logistic problems of using hydrogen fuels in motor vehicles. Ammonia can be stored under moderate pressure at ambient temperatures. (Its physical properties are closely similar to those of liquid propane.) It can be packaged in a volume compatible with present automobiles. It is used as a fertilizer in quantities of over 100 million tons per year so that facilities for its storage, safe handling, transportation and distribution are available worldwide. It could be an economical replacement for gasoline if the foreseen costs of air pollution and global warming caused by fossil fuels are included in the economic evaluation

[32]


Abstract : Ammonia can be used successfully as a spark ignition engine fuel and at presently existing compression ratios, if introduced as a vapor and if first partly dissociated to hydrogen and nitrogen. Under such circumstances little engine modification is necessary other than a means for flow control of the ammonia and adjustment of the spark timing. Maximum experimental power output for ammonia was 72 per cent of that for iso-octane. This result compares favorably with a theoretically predicted output, when adjusted for 5 per cent hydrogen dissociation, of 75 per cent. Specific fuel consumption using ammonia is increased by a factor of 2 over that of hydrocarbon when compared at peak power and 2-1/2 times when compared at maximum economy. Hydrogen concentration in the fuel feed is a critical factor for successful operation on ammonia as fuel. Minimum concentrations appear to be 4 to 5 per cent by weight at intermediate engine speeds of 1800 rpm. Engine performance rapidly falls if less than minimum concentrations of hydrogen are used. This seems to relate to the self-generating character of the ammonia decomposition during the compression and combustion processes. Performance factors such as are influenced by engine speed, spark timing and manifold pressure are not far different with ammonia than with hydrocarbons as long as minimum amounts of hydrogen are inducted as a part of the fuel flow. [33]

ammonia as a fuel re instated[edit]

I don't see how this can be chopped out. In today's situation alternative fuels are of the highest priority and ammonia is a key candidate. Therefore more detail is required albeit the entry may need editing.

If fags get a mention then fuel should get a much greater mention IMHO Engineman (talk) 17:20, 23 July 2008 (UTC)

If you want to talk about it put it in the section don't create a whole new article about it. Especially such a poorly written one. It's a waste of time for you and for others.
And next time try not to use such a vulgar word. Just because you don't like something doesn't mean you cant be respectful --NefariousOpus 09:32, 23 August 2008 (UTC)
I would assume that Engineman was using "fags" to refer to cigarettes (British usage), not homosexuals (U.S. usage)! Physchim62 (talk) 10:34, 23 August 2008 (UTC)
Sorry bout that one. Just so used to hearing it the derogatory way. I cant stand bigotry --NefariousOpus 10:56, 23 August 2008 (UTC)
No harm done by a simple misunderstanding, I'm sure! To get back to the subject of discussion, I wouldn't say that ammonia is a key candidate for alternative fuels—there are formidable economic problems in its widespread use—but neither does this use fall under WP:FRINGE. I've added a note about the combustion products to justify the fact that it is "clean" (ie, the combustion doesn't go to NOx). We mustn't let the article lose sight of the fact that the main uses of ammonia are fertilizers (~80%), plastics and fibres such as nylon (~10%) and explosives (~5%): any other uses should be classed as "minor". Physchim62 (talk) 11:41, 23 August 2008 (UTC)

It may be that the main uses are fertilers, plastics and fibres, but on the face of it ammonia is a much more likley fuel than for example hydrogen from the fact that you can readilly fit it into vehicles.

It's clearly better than hydrogen from this point of view, and overall efficiency... so why the reluctance to have an article covering the good points

The points in favour of ammonia as fuel are very clear....at one time most of europe's ammonia came from a renewable power station in Norway. Its a more efficient fuel carrier than hydrogen. We know how to make and store the stuff... it will work in engines....no need for expensive fuel cells if they ever arrive...therefore must be a candidate....

My start does of course need editing. sorry but can't find tilde on this keyboard

World gasoline consumption is around 800 billion tonnes per year, and world diesel consumption around 600 billion tonnes a year. World ammonia production is around 150 million tonnes a year, roughly ten thousand times less. To produce this ammonia takes about 1% of the world's harnessed energy resources. Yes, ammonia can be produced from renewable energy resources, but on nothing like the scale of current production, let alone the production which would be needed to replace petroleum-based fuels. You cannot "readily" fit it into vehicles, you must have cryogenic storage and expensively modified engines. Hence, I stick with my assessment that it is hardly a "key" candidate as an alternative fuel. Physchim62 (talk) 18:40, 23 August 2008 (UTC)

ammonia is way to costly! —Preceding unsigned comment added by 68.43.132.86 (talk) 23:52, 23 August 2008 (UTC)

Who cares whether NH3 is expensive or not. We editors are charged with not using these articles for original research or soap-boxing (e.g. the implication above that we owe it to society to promote its possible use as an "alternative fuel. --Smokefoot (talk) 02:28, 24 August 2008 (UTC)

Dear Physchim62 re below.

Physchim62 said:

World gasoline consumption is around 800 billion tonnes per year, and world diesel consumption around 600 billion tonnes a year. World ammonia production is around 150 million tonnes a year, roughly ten thousand times less. To produce this ammonia takes about 1% of the world's harnessed energy resources. Yes, ammonia can be produced from renewable energy resources, but on nothing like the scale of current production, let alone the production which would be needed to replace petroleum-based fuels.

Engineman comment on above: Yes agree with the above points and there is no way that any other potential alternatives can replace gasoline and diesel and that point needs to be more generally recognised.....But the same argument applies with much greater force to the use of hydrogen which is routinely touted as an alternative liquid fuel. Yet hydrogen has much greater disadvantages than ammonia. Whilst hydrogen can be produced with the same sort of energy efficiency from renewables or nuclear as ammonia it has much greater barriers to use age - namely you can't store enough of the stuff in the vehicle except under enormous pressure and with the loss of energy in compressing and cooling the gas. It appears to me that ammonia can be a replacement for the very small residual vehicle population we will be forced to adapt to as oil supplies diminish.

Physchim62 said: You cannot "readily" fit it into vehicles, you must have cryogenic storage and expensively modified engines.

Engineman comment on above: Both these points do not appear to be true if you read the references included above. Ammonia can be stored in pressure vessels and is routinely carried around the country in tankers. IT readily liquefies at lowish temperatures hence its use in refrigeration. It can be burnt in unmodified engines merely by the addition of 5% hydrogen pilot fuel...which quantity can be carried in a vehicle, unlike say 100% hydrogen.

It seems to me that therefore it is a much more feasible potential fuel replacement than hydrogen - albeit as you rightly say, it is never going to replace fossil oil, but then nothing on the horizon, in particular hydrogen can.

Regards

engine man

This is a very interesting discussion. I had no idea that people were contemplating using ammonia as a fuel for internal combustion engines! I think it can be mentioned in the article, as long as it is not given excessive weight and is presented fairly. Some obvious questions that would need to be answered are: is it worth risking the use ammonia as a fuel for vehicles, given that it is smelly/toxic/corrosive? Also, like hydrogen, ammonia is mostly obtained from natural gas. It should be pointed out that it is not carbon-free and not renewable, at least until it becomes generally cheaper to obtain hydrogen from other sources. --Itub (talk) 10:51, 25 August 2008 (UTC)


When I came across the idea it seemed completely mad to me, but when i dug a little deeper it seems to make a lot of sense. Well a lot more sense than using hydrogen, and possibly more sense than batteries. The key point is of course that it only makes any sense if the hydrogen comes from renewable sources. That then means a huge investment in renewable power (or nuclear) which means it will never be able to replace present quantities of fossil fuels, but the limited use we will have to make of liquid fuels could more sensibly come form ammonia than hydrogen.

It seems that the issue of odour and toxicity is pretty minor - it is not in fact very toxic by comparison to say LPG, is routinely carried around in large tankers at room temperatures.

Engineman

Have you smelled concentrated ammonia? ;-) I've never handled anhydrous liquid ammonia myself, but the saturated aqueous solution is nasty enough for me. While the toxicity itself is not huge, ammonia can cause chemical burns, and inhaling it in large concentrations can be deadly. Of course ammonia is carried around in huge amounts, safely enough, as it is one of the top products of the chemical industry. My worry is that while you can more or less control the safety of the relatively limited number tankers, trains, trucks, and pipelines that transport ammonia, the risks will become much higher if you put a hundred million ammonia-powered vehicles on the road. Accidents and leaks will happen. My question is whether the risk will turn out to be acceptable. I'd be interested in learning more about the types of fuel tanks and pumps that would be used. --Itub (talk) 14:13, 26 August 2008 (UTC)

Funnily or stupidly enough i have smelled ammonia - its like being punched very hard in the nose. But that is pretty minor compared to what happens if you are in a car and the fuel tank full of petrol ruptures, or presumably a tank of LPG.

One of the references above indicates that the death per tonne of ammonia carried is less than that per tonne of LPG for example. Of course you have to compare the numbers of deaths that already occur in traffic accidents, with the increased number form carrying ammonia compared to say petrol - not significant i would guess.

One possibility with using Ammonia as a fuel is that it can be broken down into Hydrogen and Nitrogen before being supplied to the engine. This is an endothermic process - the reverse of the Haber Process. If it could be set up to absorb heat from the engine exhaust, the hydrogen produced would have a greater calorific value than the ammonia from which it was produced and would give a useful improvement in the overall efficiency.

As stated elewhere, pure ammonia has a low flame speed which is not ideal in an i.c. engine, however pure hydrogen has a very high flame speed, which is also not ideal. A mixture of the two gases could work quite well. —Preceding unsigned comment added by Crackpot1 (talkcontribs) 19:43, 1 May 2009 (UTC)

more ammonmia as a fuel[edit]

Comments from the Iowa energy centre on comments on the wind talk page:

Thanks for that Terratornis.....I personally think the whole hydrogen / battery / capacity thing is a scam to divert attention. Hydrogen is never going to be an answer. But with ammonia you could literally start running vehicles on it .....well ....today.....It doesn't require decades to turn the technology over as it will more or less run in existing engines with a bit of modification - so i am led to believe John

Well, ammonia has some problems beginning with its toxicity, and the fact that even a small leak of ammonia renders the atmosphere unbreathable for hundreds of meters. This is a tremendous exaggeration. Ammonia is lighter than air and will dissipate in moments, unless it combines with humidity in the air to form ammonium hydroxide droplets. "Hundreds of meters" is just flat out false. See http://www.ammonia-safety.com/in-action.htm and attached safety report. Every vehicle with a tankful of ammonia becomes a weapon of mass destruction. This fellow has watched too much TV. Of course a tank full of petrol is almost as destructive. But even if ammonia could work in existing cars with affordable modification, there is still the difficulty in building the infrastructure to handle it in large volumes. Same would be true with any fuel, e.g. ethanol, hydrogen, CNG, or for that matter electric cars. A possible solution is "at-home" refueling, which technically achievable in principle with electric, hydrogen, and ammonia. If you've ever been near an ammonia plant, you know there are inevitably some leaks. Having ammonia filling stations on every street corner could make living in a city almost intolerable. He's making up the story as he goes along. Ammonia is dangerous even when handled by professionals. It's hard to imagine what technology for handling ammonia could be consumer-proof. There are 800 retail ammonia outlets (I.e. fueling stations) in Iowa alone to serve N-fertilizer needs. And, with an excellent safety record. However, even apart from fuel a lot of ammonia goes to fertilizer today. Excess wind power could generate renewable ammonia for agriculture and chemical industry use, sparing natural gas which could then be used for transport until it runs out. The fertilizer part is true, of course. See for instance, www.freedomfertilizer.com . The problem is that natural gas is not a good automotive fuel since it can't be stored as a liquid. Has to be stored as a high pressure gas. But, we agree, we'd like to see the NH3 produced with something other than natural gas, if only for greenhouse gas (CO2) emission reasons. I have some notes at User:Teratornis/Energy#Renewable ammonia. One way to solve the intermittency problem for wind is to build more capacity than you need, and use the excess power during windy spells to generate hydrogen to feed a renewable ammonia industry. This is a good idea, and is being pursued by several organizations. Also for solar and hydro. Both hydrogen and ammonia are easy to store in industrial volumes. Wrong, big time false. Hydrogen is terrible to store because of its low volumetric energy density. Hydrogen storage difficulties are the Achilles heel of the Hydrogen Economy. A renewable ammonia industry could soak up tremendous amounts of excess power and generate a valuable product. Neither hydrogen nor ammonia are convenient (yet) to use as a portable energy carrier, but lots of people are working on hydrogen storage at least. --Teratornis (talk) 23:12, 25 November 2008 (UTC)

If you can get natural gas in and out of cars without much of a leak - I would have thought the same could be done with ammonia? The stuff is tankered around USA in vast quantities and injected into the soil without much difficult.Engineman (talk) 02:19, 26 November 2008 (UTC) www.ammoniafuelnetwork.org, and the AFN conference proceedings at http://www.energy.iastate.edu/Renewable/ammonia/ammonia.htm .


The primary commercial effort on NH3 engines is being led by the Hydrogen Engine Center and Grannell, Gillespie, Stack LLC. Both groups have papers in the 2008 conference proceedings at the link above. Top automakers are discussing ammonia engines, but are not discussing it publicly. It appears that the market for NH3 internal combustion gensets (zero emission backup and peaking power) will develop before that for highway vehicles. Two top generator manufacturers were represented at the recent meeting in Minneapolis. Fuel cells are on the drawing board, but as you say, NH3 engines are available today !Engineman (talk) 10:57, 27 November 2008 (UTC)

Best regards.

John

more ammonia as an engine fuel[edit]

This link demolishes any concerns about the practicality and safety of ammonia. http://www.claverton-energy.com/download/163/.

This is another good link:

http://www.thecuttingedgenews.com/index.php?article=799

Can someone copy the rather good bus picture in?

Regarding the fact that we would need to increae the production of ammonia by a factore of 10,000 - well you can of course go back in history no more than 100 year and find a point where gasoline useage was less than some point in the futre by a factor of 10,000.Engineman (talk) 16:25, 27 November 2008 (UTC)

This article is about ammonia, the combustion of which is already mentioned in two places. In terms of a more suitable place where you can "demolish" concerns about practicality etc then Alternative energy would be a suitable home for your reporting. Wikipedia presents a convenient vehicle for exploring or advocating ideas, but then there's [[[WP:SOAP]] which is one of the most central guiding aspects of this project. IMHO.--Smokefoot (talk) 22:12, 27 November 2008 (UTC)

Fair comment, but ammonia isnt an alternative energy source, it is a potentially a convenient energy carrier - teh pros and cons of which can be usefully discussed in this article withouth soap boxing I beleive. Engineman (talk) 03:26, 28 November 2008 (UTC)

If you think it adds insight into this topic, could someone add this hyperlink to the NH3 as a fuel discussion. I would do this myself but I am new to wiki and still learning the ropes: http://www.elucidare.co.uk/news/ammonia%20as%20h2%20carrier.pdf —Preceding unsigned comment added by Dghn (talkcontribs) 23:04, 24 February 2010 (UTC)

Thanks, but it looks too promotion of a company and has a few verifiable sources within. Materialscientist (talk) 23:53, 24 February 2010 (UTC)

coments on Physchim62 comments[edit]

Physchim62 said: COMMENTS FROM ENGINEMAN AND WILLOTHEWISP World gasoline consumption is around 800 billion tonnes per year, and world diesel consumption around 600 billion tonnes a year. World ammonia production is around 150 million tonnes a year, roughly ten thousand times less. To produce this ammonia takes about 1% of the world's harnessed energy resources. Yes, ammonia can be produced from renewable energy resources, but on nothing like the scale of current production, let alone the production which would be needed to replace petroleum-based fuels. THIS IS JUST WRONG. I SUSPECT PHYSCHIM62 HAS SAID "TONNES" WHEN HE MEANS GALLONS. THE US REPRESENTS 1/4 OF THE WORLD'S OIL CONSUMPTION AT APPROXIMATELY 20 MILLION BARRELS A DAY. 365 DAYS A YEAR. ABOUT 70% OF THAT GOES FOR TRANSPORTATION USE. ASSUME, FOR SAKE OF ARGUMENT THAT A BARREL (42 GALLONS) YIELDS 42 GALLONS OF GASOLINE OR DIESEL. SO, THAT WOULD BE 307 BILLION GALLONS TOTAL OF OIL AND DIESEL PER YEAR FOR THE US. THEN, THE WORLD WOULD BE 4X THAT OR 1230 BILLION GALLONS ANNUAL GASOLINE AND DIESEL WORLDWIDE. AT A COMPOSITE DENSITY OF ABOUT 0.8 KG/LITER, THAT WORKS OUT TO 3.7 BILLION METRIC TONS PER YEAR, A FAR, FAR CRY FRO 800 + 600 = 1400 BILLION TONNES. PHYSCHIM62 IS RIGHT ABOUT THE WORLD ANNUAL NH3 PRODUCTION. I USUALLY QUOTE 130 MILLION TONNES, BUT IT'S PROBABY GONE UP SOME. I DON'T KNOW WHERE PHYSCHIM62 GETS THE 1% FIGURE FOR THE FRACTION OF TOTAL WORLD ENERGY CONSUMPTION TO PRODUCE NH3. I SUSPECT IT'S ALSO WRONG, THOUGH. IT TAKES ABOUT 9 TO 10 MWH ENERGY TO MAKE A TONNE OF AMMONIA WITH NATURAL GAS. (AND THAT TONNE OF NH3 CONTAINS 5.2 MWH (LHV).) IT TAKES ABOUT 12 MWH TO MAKE A TON OF AMMONIA USING AN ELECTROLYZER TO SUPPLY THE H2. [BTW, OUR PATENT PENDING SSAS PROCESS OF DIRECT AMMONIA SYNTHESIS FROM WATER AND AIR (NO INTERIM H2 FORMATION) USES ONLY 7.5 MWH PER TONNE. I'VE ATTACHED A BRIEFING.] SO, BOTTOM LINE IS YES, OF COURSE, NH3 PRODUCTION WOULD HAVE TO BE INCREASED MULTI-FOLD TO BEGIN TO ADDRESS A SIGNIFICANT FRACTION OF OIL CONSUMPTION. BUT NOT THOUSANDS OF TIMES, LIKE PHYSCHIM62 SUGGESTS. THERE IS PLENTY OF UNTAPPED WIND AND SOLAR TO PROVIDE THE ENERGY FOR THE NH3 PRODUCTION INCREASE. Engineman comment on above: Yes agree with the above points and there is no way that any other potential alternatives can replace gasoline and diesel and that point needs to be more generally recognised.....But the same argument applies with much greater force to the use of hydrogen which is routinely touted as an alternative liquid fuel. Yet hydrogen has much greater disadvantages than ammonia. Whilst hydrogen can be produced with the same sort of energy efficiency from renewables or nuclear as ammonia it has much greater barriers to use age - namely you can't store enough of the stuff in the vehicle except under enormous pressure and with the loss of energy in compressing and cooling the gas. It appears to me that ammonia can be a replacement for the very small residual vehicle population we will be forced to adapt to as oil supplies diminish. YES, ALL OF US NH3 FUEL ADVOCATES ARE REALLY HYDROGEN ENTHUSIASTS, BUT PRAGMATIC ONES. WE KNOW THAT THE MAIN PROBLEM IS H2 STORAGE, WHICH NH3 (ACTUALLY TRADEMARKED "THE OTHER HYDROGEN") SOLVES. OF COURSE, HYDROGEN HAS OTHER PROBLEMS, SUCH AS FUEL CELL COST AND LIFETIME, BUT WE DON'T NEED TO GO THERE. Physchim62 said: You cannot "readily" fit it into vehicles, you must have cryogenic storage and expensively modified engines. THIS IS BALONEY, UNLESS HE'S TALKING ABOUT HYDROGEN AND NOT NH3. AMMONIA IS A HYDROGEN-DENSE LIQUID AT ROOM TEMPERATURE AND 125 PSI. Engineman comment on above: Both these points do not appear to be true if you read the references included above. Ammonia can be stored in pressure vessels and is routinely carried around the country in tankers. IT readily liquefies at lowish temperatures hence its use in refrigeration. It can be burnt in unmodified engines merely by the addition of 5% hydrogen pilot fuel...which quantity can be carried in a vehicle, unlike say 100% hydrogen. ACTUALLY 100% NH3 SI IC ENGINES HAVE BEEN RUN, BUT CRACKING ABOUT 5% TO H2 ON THE WAY TO THE ENGINE MAKES IT RUN BETTER, AND HAVE MORE COMPLETE COMBUSTION. AND, NH3 WILL BURN IN CI DIESEL ENGINES IF THERE IS 5% OF A HIGH CETANE ADDITIVE, SUCH AS BIODIESEL OR DME.

Damages of Ammonia to Human body[edit]

The organisation of the chapter Safety Precautions for Ammonia appears misleading and not consistent. The first statement that appears under the section Toxicity and storage, it says "The toxicity of ammonia solutions does not usually cause problems for humans".

While under the section Household use it says: "These solutions are irritating to the eyes and mucous membranes (respiratory and digestive tracts), and to a lesser extent the skin"

At the end of the whole paper under SAFETY section, it says: "Although ammonia is regulated in the United States as a non-flammable gas, it still meets the definition of a material that is toxic by inhalation".

I think consistency/coherence of Safety info should be checked and amended.

Regards, Paolo —Preceding unsigned comment added by 80.79.80.103 (talk) 10:55, 11 December 2008 (UTC)

Detection and determination section references[edit]

The research papers described in this section are far too advanced to be included in the main body of an encyclopedia article on a general topic like ammonia. I suggest that they be moved to the end of the article in a "Further reading" section, or a new article on ammonia in astronomy be created. Silverchemist (talk) 18:36, 16 December 2008 (UTC)

Section headings[edit]

Why are there two section headings with the word "safety"? These seem like they could be merged. Wizard191 (talk) 01:00, 6 June 2009 (UTC)

Done.—Tetracube (talk) 02:24, 6 June 2009 (UTC)
Thanks. Wizard191 (talk) 02:37, 6 June 2009 (UTC)

Maser[edit]

should there be a mention of the ammonia maser and/or link to page on masers on this page?Brokencalculator (talk) 11:15, 17 July 2009 (UTC)

GA Reassessment[edit]

This discussion is transcluded from Talk:Ammonia/GA1. The edit link for this section can be used to add comments to the reassessment.

This article is being reviewed as part of the WikiProject Good Articles. We're doing Sweeps to go over all of the current GAs and see if they still meet the GA criteria. This article was awarded GA-status back in 2007, so I will be assessing the article to ensure that it is still compliant.Pyrotec (talk) 11:37, 21 July 2009 (UTC)

Initial comments[edit]

This appears to be quite a comprehensive article, but the main problem is lack of WP:verify, i.e. lack of in-line citations.

Some sections, such as History, Ammonia's role in biological systems and human disease and Detection and determination are adequately referenced, but other sections are not.

For instance:

  • In Structure and basic chemical properties - only the second para is referenced.
  • Biosynthesis is unreferenced.
  • Properties mostly unreferenced.
  • Formation of other compounds - unreferenced.
  • Ammonia as a ligand - unreferenced.
  • Toxicity and storage information.

There are more, but I'm putting the review On Hold at this point.16:41, 26 July 2009 (UTC)

Delisting.Pyrotec (talk) 19:41, 8 August 2009 (UTC)

In food production?[edit]

The article says that ammonia is used as "a precursor to foodstuffs" but that does not appear to be elaborated on. I bring this up because I came to the article trying to understand the effects of ammonia used to treat beef as described in this NYT article. Personally, I was curious what the precedents and effects of this practice are, how widespread it is, and other examples where ammonia is used in the production of food that is commonly consumed. 98.242.13.59 (talk) 16:25, 4 October 2009 (UTC)

Synthesis and production[edit]

The text begins by saying that The People's Republic of China produced 28.4% of the worldwide production (increasingly from coal as part of urea synthesis), and then lists where the hydrogen comes from by saying that Today, the typical modern ammonia-producing plant first converts natural gas (i.e., methane) or liquified petroleum gas (such gases are propane and butane) or petroleum naphtha into gaseous hydrogen.

This is a contradiction: either China is the top producer (so coal should be listed as the main source for hydrogen gas) or China does not use coal to produce hydrogen/ammonia/urea. Albmont (talk) 12:06, 14 October 2009 (UTC)

There's no contradiction here. China has started to use coal gasification as a source of hydrogen, yes, but it is still only a small proportion of Chinese production, let alone global production. This is why the development of coal as a hydrogen source was notable in the news item that forms the reference for the statement in the article. That news item lists three Chinese plants using coal, which together account for 1% of world ammonia production capacity. The "typical modern ammonia-producing plant" still uses oil or (more usually) natural gas as the source of hydrogen. Physchim62 (talk) 12:40, 14 October 2009 (UTC)
Ok, I see. Historically, I think ammonia production began with coal, in Germany, during World War I, so I thought coal was still a major source of H2 for ammonia. Albmont (talk) 14:21, 14 October 2009 (UTC)
At the moment, no, although I (personally) wouldn't rule it out as a future source. Electrolysis of water was also a significant source of hydrogen between the wars (see Vemork), and might be in the future. Physchim62 (talk) 14:28, 14 October 2009 (UTC)

*All* nitrogen in manufactured products? Really?[edit]

The article makes the somewhat hyperbolic claim that 'The entire nitrogen content of all manufactured organic compounds is derived from ammonia.'. However, prior to the worldwide adoption of the Haber process there were various methods for producing nitric acid via electrical arc, and some of this nitric acid would have been directly incorporated into such materials as collodion or early nitrate film, some few remnants of which no doubt still exist. It's also likely that even today some small quantities of nitrogen find their way from mineral deposits (such as sodium nitrate) into manufactured organic compounds, without first undergoing a transformation into ammonia. Finally, there are various nitrogen-containing plant-derived compounds, such as oripavine and papaverine, which are used to synthesize nitrogen-containing organics - again without any ammonia involved. The claim seems overbroad. Bbartlog (talk) 22:14, 2 November 2009 (UTC)

Great catch: the comment does seem hyperbolic. But its probably true except for a handful of specialized processes that transform natural products, e.g. leading to semi-synthetic drugs like oripavine. It is possible that extracted glycine is used etc. If you have more info, supply it or speculate on it. It's just a question of scale. How's 'Virtually all manufactured organic compounds are derived from ammonia."--Smokefoot (talk) 00:11, 3 November 2009 (UTC)
Agree with both and compromised the phrasing in the article :-) Feel free to correct. Materialscientist (talk) 01:12, 3 November 2009 (UTC)

Solubility[edit]

The page appears to have an error regarding the solubilities in the right-hand table. It gives the values:


1176 g/100 mL (0 °C)
702 g/100 mL (20 °C)
88 g/100 mL (100 °C)

Should these not be litres rather than gm, i.e. 1 litre of water will dissolve 702 litres of ammonia gas at 20C? See for example the bottom of this page.

The solubility quoted on the ammonium hydroxide page is "At 15.5556 °C, the density of a saturated solution is 0.88 g/mL and contain 35% ammonia by mass, 308g/L w/v" or 30.8g/100 mL at 15.6C (60F).

George Dishman 20:36, 13 January 2010 (UTC) —Preceding unsigned comment added by GeorgeDishman (talkcontribs)

Solubilities!!![edit]

The solubilities of ammonia were given as

| Solubility = 1176 g/100 mL (0 °C)
702 g/100 mL (20 °C)
88 g/100 mL (100 °C)

Without checking for the verified numbers, these are clearly off by an order of magnitude. I checked a few sources and saw that changing the values to

| Solubility = 117.6 g/100 mL (0 °C)
70.2 g/100 mL (20 °C)
8.8 g/100 mL (100 °C)

was within reason. Please forgive me for not verifying the exact figures before making the change, but the inaccuracies were gross enough that I thought an immediate edit was not untoward. Gaedheal (talk) 22:01, 5 February 2010 (UTC)

Thank you for fixing that obvious mistake (it is quite common in WP chemistry articles perhaps because of confusion between x/1OO mL and x/L). I'll try to find refs shortly. Materialscientist (talk) 00:50, 6 February 2010 (UTC)

What does this mean?[edit]

"... however it was acquired by the alchemist Basil Valentine." I haven't a clue what it means, how do you acquire ammonia, you either isolate it or purify it, or characterize it .... --Richard Arthur Norton (1958- ) (talk) 23:32, 30 March 2010 (UTC)

"Acquired" smacks of alchemical terminology. In fact good ole' Basil Valentine is mentioned in the preceding paragraph under his Latin name of Basilius Valentinus, so we can say that we have given him credit, whatever the modern-day alchemists might say. Thanks for picking this one up. Physchim62 (talk) 00:43, 31 March 2010 (UTC)
I guess it just needs to be re-added back in the previous Alchemy section, and not tucked into the 1700s section. It just seemed out of chrono order. Richard Arthur Norton (1958- ) (talk) 04:08, 31 March 2010 (UTC)

I am glad to learn that ammonia is not flammable except when it is It also gladdens my heart that all (synthetic?) organo nitrogen compounds, except for the ones that aren't, are made with it. Both qualified universals. Here's a suggestion: Most, the vast majority, almost all. Also, Vapor Pressure at STP should be included. FWIW71.31.145.204 (talk) 02:46, 28 May 2010 (UTC)

This article says neither that ammonia is not flammable nor that all organonitrogen compounds are made with it. Please be more specific and coherent. Materialscientist (talk) 03:06, 28 May 2010 (UTC)

acidity[edit]

As an electronegative atom, the N-H bond of neutral ammonia is also acidic. I believe (from the sodium amide) article, this should be 38. Can someone please add this back?

There's no reason to have pKa and pKb values for the same acid-base reaction. It's also confusing.


Shouldn't pkB should be for the reaction NH3 + H2O ---> NH4+ + OH- (pK = 4.76) and that pKa NH3 + H2O ---> NH2- + OH- (pK = 38)? John Riemann Soong (talk) 06:35, 9 October 2010 (UTC)

Specific Heat Capacity[edit]

There is a claim in this article that ammonia has the highest specific heat capacity of any known substance. This cannot be true, especially since It's molecule has only 4 atoms (in general,specific heat capacity increases with number of atoms since there are more vibrational modes). I would like to delete this statement, especially since there is no citation link. Pjbeierle (talk) 20:42, 20 February 2012 (UTC)

ammonia[edit]

the dog next door goes crazy when a golf-cart or 4wheeler goes by tries to bite tires he has already broken one of k-nine teeth i was thinking about a water gun with mild solution of ammonia & water to break this habit? — Preceding unsigned comment added by 174.56.203.136 (talk) 19:54, 5 May 2012 (UTC)

Original research published in Court Documents?[edit]

I did forensics on Olympic Cold Storage case, explosion caused several deaths. Industrial facility using Ammonia refrigerant that was refilled (topped off) with Freon, mixture exploded when it cycled through the compressor. Freon being the oxidizer. Interesting that propane flame energy source instead of mechanical energy can be used for portable Ammonia refrigerator. Shjacks45 (talk) 19:46, 2 January 2013 (UTC)

/* Synthesis and production */ Vemork says otherwise[edit]

According to this august compendium, Vemork "was built to power a factory producing artificial fertilizer by a new method invented by Kristian Birkeland". That was the Birkeland–Eyde process, which does not involve the electrolysis of water. Moreover that process produces nitrates via nitric oxide, not ammonia. Qemist (talk) 00:47, 5 February 2013 (UTC)

I'm sorry, you might be right, but you can't use wikipedia articles to justify your argument, especially article such as Vemork which is almost entirely unreferenced; but you might be able to use some of the references quoted by the wikipedia articles (see later).
  • Firstly, Wikipeidia articles, and/or articles on other sites that have been copied from wikipedia, are not regarded as WP:reliable sources to be quoted in other wikipedia articles.
  • Secondly, the Vemork article does not refer to the Birkeland–Eyde process, by name, that comes from you. There are further problems in so far as the Vemork article does not appear to have been written in accordance with wikipedia guidelines for the WP:Lead. Specially, the lead does not fully summarise the contents of the body of the article and it contains material that does not appear in the body of the article: the lead specifically states: "Vemork was later the site of the first plant in the world to mass-produce heavy water developing from the hydrogen production then used for the Haber process.", but the History section, as you pointed out above, states: "The plant, itself, was built to power a factory producing artificial fertilizer by a new method invented by Kristian Birkeland.". The article is unreferenced, apart from one statement, and neither of those statements had references to support their claims. During the first and second World Wars, and beyond, nitric acid was made from ammonia by oxidation with air by means of a platinum gauze catalyst. So, based on what the lead states, the plant could have been producing ammonia which was then converted to nitric acid and subsequently used to make fertilizer; and that is to be inferred by the use of that plant to produce Heavy water.
  • Thirdly, there is a separate article, Norsk Hydro Rjukan that does specifically mention Kristian Birkeland converting air into fertiizer, i.e.: "The Telemark power-based industry adventure started in 1902 when Sam Eyde, along with Norwegian and Swedish investors, bought the waterfall Rjukanfossen—establishing A/S Rjukanfos on 30 April 1903. The same year, on 13 February, Eyde and Kristian Birkeland had met and started working on refining the electric arc to produce an electric flame; allowing Eyde to complete his process of converting air and electricity into fertilizer. On 19 December 1903 Det Norske Kvælstofkompagni was founded, followed by Det Norske Aktieselskap for Eletrokemisk Industri (today Elkem) in 1904; both were in part owned by the Wallenberg family, Stockholms Enskilda Bank and Banque de Paris et des Pays-Bas.[2]"
  • Fourthly, the Birkeland–Eyde process wikipedia article is much better referenced than the Vemork article, but again it can't be used as a reliable source, but its references could be. The article itself states: "A factory based on the process was built in Rjukan and Notodden in Norway, combined with the building of large hydroelectric power facilities.[2]", it does not name Vemork by name. Then in the next sentence it states: "The Birkeland-Eyde process is relatively inefficient in terms of energy consumption. Therefore, in the 1910s and 1920s, it was gradually replaced in Norway by a combination of the Haber process and the Ostwald process. The Haber process produces ammonia (NH3) from methane (CH4) gas and molecular nitrogen (N2). The ammonia from the Haber process is then converted into nitric acid (HNO3) in the Ostwald process.[3]".
I suggest that you look at the original sources, possibly references 2 and 3 from Birkeland–Eyde process, to see what is stated there. Pyrotec (talk) 17:04, 5 February 2013 (UTC)
How about I just delete the unreferenced claims about Vemork from this article?Qemist (talk) 23:21, 7 February 2013 (UTC)
If you regard it as "contentious" or controversial, and since it is unreferenced you can delete it, if you like. Pyrotec (talk) 20:51, 8 February 2013 (UTC)
Consider it done. Qemist (talk) 10:28, 13 February 2013 (UTC)

Self-dissociation?[edit]

The paragraph on self-dissociation gives a value "at standard pressure and temperature" of K=[NH+
4
][NH
2
] = 10−30
. But at standard pressure and temperature, ammonia is a gas. I suppose a gas can self-dissociate a bit, but then not "like water" as the paragraph also says. Wouldn't it be more meaningful to give the figure for liquid ammonia (at standard temperature and high pressure, or at standard pressure and low temperature, for instance). David Olivier (talk) 10:50, 18 April 2013 (UTC)

I have found a reference - [1] - that states that the self-dissociation constant is 10−29
"even at boiling point", specifically at -33°C. Could someone insert it? (I don't feel confident enough in chemistry to avoid blundering.) David Olivier (talk) 08:24, 19 April 2013 (UTC)

Deoderized??[edit]

In the text, the passage: "Ammonia may be conveniently deodorized by reacting it with either sodium bicarbonate or acetic acid. Both of these reactions form an odourless ammonium salt." Implies that deoderizing ammonia turns it into a salt. Then isn't it no longer ammonia? You can't take a gas and turn it into something else, then say it's deoderized, right? 71.139.178.219 (talk) 17:42, 22 April 2013 (UTC)

True. In ordinary parlance, whatever object contained the smell, is deodorised, not the odiferous gas itself, which is impossible. Plasmic Physics (talk) 22:12, 22 April 2013 (UTC)
Furthermore, the noted reaction is correct, but not the terminology used - a rewrite is in order. Plasmic Physics (talk) 22:15, 22 April 2013 (UTC)
I am struggling with the "British English" tag when editing. The awkwardness of the infobox saying "Odor: Strong characteristic odour" is just wrong in so many ways. I am happy to acquiesce to BE spelling, but can there then be a BE infobox template so the spelling matches? Same thing about "deodourising" vs. "deodorizing". Huw Powell (talk) 00:10, 6 August 2013 (UTC)

Bond angle and length[edit]

The correct bond angle and length for ammonia should be 106.7 degrees and 101.2 angstroms as per the current addition of the CRC handbook.[1] I can also get you a literature citation if need be. I corrected the text on this page and on the data page. If someone could correct the image that goes with this article that would be great. — Preceding unsigned comment added by 130.215.189.43 (talk) 21:13, 18 June 2013 (UTC)

"Dilute aqueous ammonia can be applied on the skin to lessen the effects of acidic animal venoms, such as from insects and jellyfish"[edit]

There aren't any references for this and it's a bit of a stretch to claim this without any sources. Can someone hunt down an answer to this? 69.242.157.38 (talk) 22:40, 15 September 2013 (UTC)

Solubilities without units useless[edit]

Solubilities on the right given in %, without saying whether it is %w/w or %vol. Useless. As useful as saying a car is going 30 without saying whether km/h or mph. 84.72.10.174 (talk) 17:33, 15 December 2013 (UTC)

It's in %w/w. See http://www.engineeringtoolbox.com/gases-solubility-water-d_1148.html: from the graph, at 0°C about 900 g of the gas dissolve in 1 kg of water, which gives a concentration of 900/1900 = 47%. I added this to the page. Chrom69 (talk) 11:59, 29 August 2014 (UTC)

formula for ammonia NH3 not NH2[edit]

On my screen the formula for ammonia looks like NH2 not NH3 - perhaps the bottom part of 3 is cut off? regards, Colin 124.171.134.178 (talk) 04:02, 19 February 2014 (UTC)

Wrong redirection[edit]

When we search Ammonium Nitride I want to find the respective Ammonium Nitride[2], whose formula is (NH4)3N and not the Nitrogen Hydride (NH3), as this link takes me to. I see so many information here, and no one noticed we are wrong redirected. Claudio Pistilli (talk) 21:53, 20 August 2014 (UTC)

Moderate or weak?[edit]

The article says

Ammonia is moderately basic

but two paragraphs later, states

Ammonia is considered to be a weak base.

Christopher Ursich (talk) 00:14, 20 March 2016 (UTC)

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Fertilizer[edit]

"30% of agricultural nitrogen in the United States is applied as anhydrous ammonia".

How does that actually work, then ? Spraying a boiling, toxic, cryogenic liquid all over the farm would seem to be a process fraught with difficulties, unless the aim is some kind of re-enactment of Flanders, 1917. How do they actually do this ? Lathamibird (talk) 16:30, 26 October 2016 (UTC)

Ammonia use[edit]

Under the heading Fertilizer under Uses, it states that "Globally, approximately 88% (as of 2014) of ammonia is used as fertilizers..." and cites the US Mineral Commodities Summaries. In this paper though, it says "Approximately 88% of apparent domestic ammonia consumption was for fertilizer use" domestic meaning the USA. The USA has yet to conquer the rest of the world so for now I assume "globally" also refers to countries outside of the USA.

[3]

Azane[edit]

Ammonia is the simplest azane, but is it really alternatively named as azane? Also, the term azane is not listed in the other name section. JSR (talk) 14:39, 28 February 2017 (UTC)

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Imperial Units[edit]

I'm not sure of the Wikipedia policy on SI Units, but in a science article is it really necessary to transpose the estimated annual production into Imperial units. Especially a unit like the Ton where the obsolete English unit isn't even the same as the unit used in North America.

Andypreston (talk) 08:37, 21 August 2017 (UTC)

  1. ^ CRC Handbook of Chemistry and Physics, 94th ed. http://www.hbcpnetbase.com. Page 9-26. Retreived June 18, 2013.
  2. ^ Endmemo
  3. ^ https://minerals.usgs.gov/minerals/pubs/mcs/2016/mcs2016.pdf