ammonium nitrate

[zakmaster524]

I happen to have a place where i have access to ammonium nitrate very close by. Is AN used for anything in pyrotechnics? If so, how?

thanks

zak

[Niladmirari]

Fountain:

 

AN - 75%

C - 15%

Ti or Fe3C - 10%

K2Cr2O7 - 3%

 

You can add vaseline (petrolatum) - 3% for good pressing.

Edited December 28, 2014 by Niladmirari

[ddewees]

Large salutes, ie. IED's.

[Arthur]

Very few uses, but if possession is not restricted in your locality I'd collect maybe a couple of hundred grammes. If nothing else, it's a fertiliser for green plants!

[marks265]

Add a little bit of fuel oil and put a fire cracker on top and light it. Report back with what happens.

[pyrojig]

AN has the ability to make composite rocket fuels......but are finiky to store( due to heat changes effecting the fuel grain) . Also shooting targets are main use of AN. Just the simple mix Amonal is what is used in most all large rifle targets. Other than that it is a waste of time trying to use it in pyro . .................................BUT...................... if your have trouble getting Kno3 or other oxidizers , you could use this AN as " trading stock" and obtain what you want via barter. .....Just a thought..

[GalFisk]

You can make Negative X (no practival uses, but a fun curiosity): http://www.cannonfuse.com/store/pc/Pyrotechnic-Projects-Negative-X-Start-A-Fire-With-Water-d12.htm

 

You can make other nitrates by reacting it in aqueous solution with the desired metal hydroxide. Example with potassium hydroxide: http://www.nakka-rocketry.net/knsyn1.html

If necessary the hydroxide can be prepared by dissolving the oxide in water. The oxide in turn can be prepared by thermal decomposition of the carbonate or bicarbonate.

 

I seem to recall a more straightforward reaction, where the solution was boiled for some time to drive the reaction forwards by cooking off ammonia (and possibly CO2?), but I can't find any details about this at the moment.

Addon: I found the reaction mentioned in passing here: http://www.sciencemadness.org/talk/viewthread.php?tid=5(boil ammonium nitrate+metal carbonate, any ammonium carbonate formed will break down into ammonia and CO2 in the boiling water). Not sure if it works with insoluble carbonates though, or only the soluble (bi)carbonates.

 

You can also make the safest smoke bomb I've come across yet, by soaking paper in a strong solution of ammonium nitrate, and letting it dry. When ignited, the paper glows gently and gives off copious amounts of light grey smoke. Example: https://www.youtube.com/watch?v=a_E3_VPwnes

 

Ammonium nitrate is hygroscopic, meaning it absorbs moisture from the air. Keep it and anything you make with it dry and in a well sealed container.

[ddewees]

Cool smoke bomb, I'll have to try that. I wonder why he wrapped it in foil though.

[AldoSPyro]

Cool smoke bomb, I'll have to try that. I wonder why he wrapped it in foil though.

Probably to have it burn only out of the ends, causing more pressure and denser smoke.

[taiwanluthiers]

Not much... AN absorbs water from the air so if you live anywhere with humidity problem, it turns into mush. Good for exploding targets... which isn't really much (with regards to display pyro). They have been used as some kind of a propellant (called Ammonpulver) but it has the problem of absorbing moisture, so it fell out of favor.

[ddewees]

It's good for ice packs...

I had to try it to see for myself, and it works. Without using Google though, I'm still at a loss to understanding why. Things heating up in a reaction makes sense... cold on the other hand is quite amazing.

[FlaMtnBkr]

Instead of an exothermic reaction that releases heat it is an endothermic reaction that absorbs heat, or energy, to drive the reaction forward. The absence of heat is cold.

[Jakenbake]

DD What I think is weird with it is after it gets cold dry it out then add more water and it gets cold again... Just seems to me like it should only work once and done.

Edited December 29, 2014 by Jakenbake

[FlaMtnBkr]

Oh, and the reason the newspaper is covered in foil is probably to slow down the absorption of water. It makes a great smoke bomb but has to be used immediately. It doesn't need the foil to work. I roll the news print up into a cylinder and stick a fuse in the center. It starts out slow but then starts to billow out smoke from the center almost like it has a nozzle. Pretty neat but not very practical.

 

I soak the paper in a saturated solution of AN and lay in the sun to dry. In the direct sun it dries pretty quick. But roll it up and use it fast.

[FlaMtnBkr]

Jake, it has to do with the energy required for a phase change. Some have positive energy, some negative. If you dry it out so it changes phases and goes back to a solid, it requires the same heat input (energy) to dissolve into a liquid. It's been a long time and don't remember all the correct terms. Edited December 29, 2014 by FlaMtnBkr

[ddewees]

Right... good point, forgot about that. Saying something is cold isn't really as accurate as saying "less warm". I heard that mentioned while watching a program on absolute zero, I believe.

 

My wife, when those cold packs wear off, she puts them in the freezer to fix them.

[Mumbles]

It's the dissolving that make it's cold. Potassium nitrate actually does the same thing, to a lesser extent. You notice it more when wetting large batches of polverone and streamers. It is a little easier to think about if you think of temperature as the average kinetic energy of a system. In simple terms, it takes energy to turn solid ammonium nitrate into dissolved ammonium nitrate. It will happily just absorb energy from it's surroundings to complete it's solvation. The absorption of energy manifests itself in the form of heat being absorbed (temperature going down). The energy is transferred from temperature to energy associated with keeping things dissolved. As a converse, if you evaporate the water, you actually have to put this energy back in before it's totally solid/dry. Think of those heat packs you boil and let cool. If you shake them they heat back up as all the stuff inside comes back out of solution.

 

There are also a lot of things that heat up when you dissolve them. Sodium hydroxide/lye or many acids are a pretty common example of this. You can easily boil water by just mixing in these things.

 

Back to the topic at hand. Not many uses. They've mostly all been covered already.

[zakmaster524]

Alright well i have used the ammonium nitrate to make a smoke bomb, i noticed that the clouds of smoke produced are very thick and dense. Does anyone know why this is? i saw the post about the aluminum foil, but any other reasons?

[FlaMtnBkr]

Because smoke bombs make thick, dense clouds of smoke?

[TSO]

Speaking of acids and water.... ALWAYS....acid added to water...do not add water to a concentrated acid.

[zakmaster524]

well of cours...lol but this one seemed to bring out especially thick clouds

[FlaMtnBkr]

Maybe newsprint has substantial amounts of a chloride so that when it is soaked in the AN it makes some ammonium chloride. Or the AN just causes it to smolder well and make lots of unburnt fuel that act as particulates.

 

Not sure about the chemistry behind ammonium chloride but it is a common ingredient in smokes but that was a WAG.

 

A good smoke makes lots of think rich smoke that is capable of obscuring sight. Try making a zinc oxide/ HCE type smoke if you like them. It is about as good as they get and what the military uses in combat.

[zakmaster524]

alright thanks

[pyrojig]

Just be careful to not breath in the HC smoke . It is toxic, a little bit wont hurt you but breathing in a thick amount will be bad .

[andyboy]

You can make Ammonium nitrate gunpowder if you have access to the other materials listed. I did make the kind with aluminium and aluminium stearate and it worked well but I was scared to store.

 

https://books.google.se/books?id=370UwG8CuNwC&pg=PA124&lpg=PA124&dq=ammonium+nitrate+gunpowder&source=bl&ots=5pNJ-rS1Qr&sig=kWuSlDJefbfG8rn8kQ2zzHZKuks&hl=sv&sa=X&ei=RhCnVJTCNsTcywOyy4KYCg&sqi=2&ved=0CE8Q6AEwBg#v=onepage&q=ammonium%20nitrate%20gunpowder&f=false