Sciencemadness Discussion Board

Making Nitrous Oxide

AmateurEd - 28-9-2003 at 02:07

Does anyone know how to make nitrous oxide?? from air or otherwise?

Madog - 28-9-2003 at 06:11


NH4NO3 --> N2O + 2H2O

its easier to get some whipits

shadeT - 28-9-2003 at 06:33

im not a mod , but this isn't for energetic materials forum ... anyway ... you get nitrous oxide by heating up ammonium nitrate ( you can make it with nitric acid ando ammonia water ) , you can get it in cream can's - its the pressurised gas , and you can buy it in little contaniers used for filling bike tires under ways ( two contaniers cost about 5 $ in bike shops )

vulture - 28-9-2003 at 11:07

Why has this been posted in energetic materials? Furthermore, I think this topic has been discussed before.

please put it back on energetic materials!

KABOOOM(pyrojustforfun) - 29-9-2003 at 19:20

N2O is detonable! maybe it is just insensitive or something otherwise they wouldn't transport it in large amounts without special precautions (as a explosive material). it supports combustion and unlike other nitrogen oxides it's not very reactive nor that toxic so why not using it in explosive gas mixtures? eg u fill 10/11 of a plastic coca bottle with N2O and the rest with propane. cap tightly. tape a cracker to it...
(doesn't remind you of those kewlish text files?)

Iv4 - 29-9-2003 at 22:50

You sure it detonates?It's used in FAE's a lot I think.

Come to think of it you supose the nh4no3 could be decomposed by an explosion?This way the N20 would be distibuted some before it went of and a two stage initiation wouldne be needed.

no no.....

ghost711 - 1-10-2003 at 05:10

Overheating ammonia nitrate can create deadly byproducts..please do not attempt this without the proper knowledge/facts... get some whippets if you want it that bad..

Theoretic - 2-10-2003 at 04:24

You mean NO and HNO3 and the like? Yes, they are formed, but not that much, otherwise a few members would be already dead. ;)
Overheating actually produces N2 and O2 instead of N2O. ;)

JustMe - 2-10-2003 at 16:15

OK, once again from the Textbook of Inorganic Chemistry...

Very pure nitrous oxide is obtained by mixing solutions of equimolar amounts of hydroxylamine hydrochloride and sodium nitrite, warming gently if necessary:

NH2OH + HNO2 = N2O + H2O

Of course, who can get these chemicals easily these days?


[Edited on 3-10-2003 by JustMe]

BromicAcid - 2-10-2003 at 17:26

To maintain the purity of the gasses coming off the molten ammonium nitrate a heating element should be placed around the top of the flask to prevent condensation which can drip back into the flask to cause undesireable side reactions. Also bubbling the resulting gasses through a NaOH solution should remove most of the acidic oxides and running through heated copper pipe jammed full of copper wool should remove any oxygen and if you want even purer you could just throw in a cold finger along the way to take out that annoying water. Best of luck to you!

KABOOOM(pyrojustforfun) - 3-10-2003 at 20:10

thank u <i>JustMe</i>. I was very curious to know how hydroxylamine reacts with nitrous acid. I knew they react because when searching google for hydroxylamine nitrite didn't get any result.

Pyrovus - 18-2-2004 at 22:52

I know this is an old topic, but if anyone's still interested there is another [somewhat expensive] method.
If you've got some sodium metal lying around, it will react with nitric oxide at low temps to give the salt NaNO. This compound hydrolyses to give the unstable compound nitroxyl, HNO, which decomposes like so: 2HNO -> N2O +H2O.


Pyroking - 4-3-2004 at 05:52

I would have thought it would be quite dangerous making NOS out of nothing (well a few chems neway), just be carefull!!!!!;)

Nick F - 14-3-2004 at 08:22

Heat ammonium nitrate in dilute nitric acid with catalytic amounts of chloride. Not as dangerous as heating AN dry...

Esplosivo - 17-3-2004 at 03:36

When decomposing Ammonium Nitrate other nitrogen oxides will form, NOx, which are irritant, toxic and acid. I think that the best way to remove them is to bubble the gas evolved during N2O syntheses through an alkaline solution, such as sodium carbonate/hydroxide and the like.

The N2O, will bubble through the solution unreacted, while the NOx will react with the base.

N2O was first made by a certain Priestley in the 18th century by heating ammonium nitrate and iron fillings together. The gas evolved was then bubbled through water. Below is a quoted reaction:
2NO + H20 + Fe --> N2O + Fe(OH)2

[Edited on 17-3-2004 by Esplosivo]

IgnorantlyIntelligent - 17-3-2004 at 20:39

I think telling us what it will be used for is very important. If you are going to inhale it, buy whipits!!!!!!!!!!!! If you want to make it for a fun experiment, then pic a method and learn as much about it as possible and take precautions as to not hurt yourself.

tom haggen - 26-3-2004 at 11:58

Even if you did manage to make nitrous oxide with NHNO3 I can't see how you would compress it for storage.

Nick F - 26-3-2004 at 12:05

"Even if you did manage to make nitrous oxide with NHNO3"

Like I said, heat ammonium nitrate in dilute nitric acid with catalytic amounts of chloride...
No risk of explosion, no nasty NOx's...

Short term storage can be done in balloons. No need to compress it. Long term storage is pointless since it's so easy to make as and when it's needed.

My 2 Euro

axehandle - 26-3-2004 at 12:10

This is strictly about the experience of inhaling nitrous oxide.

It's not as fun as you might imagine.

1) The rush only lasts for about 15s.
1.5) The ruch isn't much fun, really.
2) You tend to fall to the floor when it kicks in.
3) You get oxygen deprivation if you're inhaling it pure.
4) You feel like a complete idiot afterwards.
5) All participants will bug you for 2 years afterwards about the sight of you falling to the floor with a stupic smile on your face, grinning like an idiot.

Trust me, I've been there, done that...

The_Davster - 26-3-2004 at 19:21

Heres a pretty easy DIY method;

thefips - 21-8-2004 at 11:45

Here is a new synthesis for N2O,which is not as dangerous as N2O from NH4NO3,and it can´t explode.I think that I have time to test it next week,then I will write my results in here.

JohnWW - 21-8-2004 at 13:07

Originally posted by thefips
Here is a new synthesis for N2O,which is not as dangerous as N2O from NH4NO3,and it can´t explode.I think that I have time to test it next week,then I will write my results in here.

Where is it? I cannot see any link or URL or attachment.

John W.

thefips - 22-8-2004 at 06:41

Sorry,it was my fault,I forgot it.But here it is:
All you need is urea,sulfuric acid and nitrous acid.

Esplosivo - 22-8-2004 at 07:26

'thefips' I'm sure it is a mistake from your part, but for the sake of precision the reaction is between nitric acid, sulphuric acid and urea, not nitrous. :)

budullewraagh - 22-8-2004 at 07:34

did i hear that the decomp of NH4NO3 yields nitric?? gas i presume, right?:o

thefips - 22-8-2004 at 08:56

Yes,my english is not really good... I meant nitric acid,HNO3.
One result from the synthesis of N2O from NH4NO3 is NO2,which is very toxic and it would be difficult to eliminate it from the N2O,because traces will be present.
But in the new synthesis it says,that the N2O is 99,9% pure.
NH4NO3 can explode from strong heating.

trinitrotoluene - 22-8-2004 at 19:10

The problems with whippets are, they're still fairly expensive. One whippet yields enough N2O gas to fill one balloon, that "hit" only produces a 15-30 second effect, then you'll have to use another whippet. So far a box of 24 whippets cost $14.99 so the cost is still very expensive.

It may be cheaper to produce your own nitrous oxide, and with proper purification method, it may be more pure than commercial nitrous from whippets.

thefips - 6-9-2004 at 08:54

The reaction works,I tested it the last 2 days.300g sulfuric acid (96%) and 60g urea were mixed in a 500ml round bottomed flask with magnetic stirring.When the urea dissolves the mixture is heated to the reaction temperature.Then 100g of 63% nitric acid are dropped in slowly(!!) with magnetic stirring.The mixture begins to bubble and the gas was washed with NaOH(aq) and collected under water in a big plastic bottle which stood in a bucket of water + Ca(OH)2.The gas was pumped out at the top of the bottle by a compressor of an old fridge and it was pumped again into the bottle,through the Ca(OH)2(aq) but in a lot of small bubbles.A lot of the CO2 was washed out.I tested the Gas and no NO2 was detected,but there was a lot of CO2 in it.

Has someone an idea to wash out the whole CO2?In the gas there are the same amounts of CO2 and N2O and it is to hard to inhale and I think the CO2 is not good for the health...

Theoretic - 12-9-2004 at 12:29

You could use sulfamic acid instead of urea. You'd then would have to only lightly heat it, and you wouldn't need sulfuric acid

thefips - 12-9-2004 at 19:23

I have stopped all my experiments on the synthesis of N2O.It is a waste of time and it is too difficult to get really pure stuff.And the costs are at the moment higher than a package of N2O capsules which can be bought in the supermarket.
It is better to spend the time on more important syntheses and perhaps other substances would be more fun... :)

sarcosuchus - 17-9-2004 at 14:26

and thers one way to make NOx that is possible if you have the eq. you will need a plasma cutter,a air compressor, a 5 gal glass water bottle, some copper tubing and misc fittings, 1-2 tig rods and some heavy guage electrical cable,a small water pump(3-5 gpm) a ph tester of some kind and a little creativity. the basic idea is to create a stable arc from the plasma cutter useing the tig rods as the ground while trying not to burn through them too fast.the water pump is to cool the plumbing so as not to have a meltdown durning the operation of the contraption the heavy cable is to complete the circuit so current will flow,copper tubing is used for carring the high temp gas to the water bottle to react with the h2o forming a more storable product:P thers only a couple of thing to remeber 1.its going to be freeking hot 2.lots o current will be in use so if theres a fire DO NOT SPRAY WATER ON ANYTHING:o and make sure thers lots of ventliation in the area you try this.the only tricky thing is postioning the tig rods in a nozzel holding pipe fitting of some kind so the arc is hot but not to hot. just something to think about

The_Davster - 17-9-2004 at 14:45

This thread is on the topic of the preparation of N2O not other nitrogen oxides.

sarcosuchus - 18-9-2004 at 19:47

my line of thinking was somthing like this
more or less what iwas thinking anyway i have a bad tendency to retrosnyth from somthing basic upwards. starting with somthing i know i can make easy.i am allways trying to do somthing in a hurry so as not to see the blue screen of death

garage chemist - 16-1-2005 at 14:23

At the moment, I'm also working on an efficient and economic method for making N2O.

I tried the method from the microscale gas chemistry page and found that it is way too slow. It takes about half an hour to convert half of the AN to N2O.
The produced gas also had a visible brown tint, so this doesn't produce NO2- free N2O either.

The method with urea + HNO3 + H2SO4 is too expensive, the same goes for the hydroxylamine + nitrite reaction.

I have settled on the method of heating pure AN as the production method. The gas evolution is rather fast, depending on the strength of the heating.
The process is carried out in a ground- glass vacuum distillation setup, where the crude N2O comes out of the vacuum adapter.
The produced water vapor condenses in the liebig and is collected in the receiving flask.

I tried this process and it works great, however, the AN must be pure.
The stuff extracted from Kalkamonsalpeter (fertilizer consisting of AN and chalk) cannot be used!
It produces a very nasty impurity which is extremely irritating to the lungs, even in very small concentrations. It is not affected in the slightest even by THOROUGH washing with NaOH. I've got no idea what this could be!
Buy some pure AN, otherwise you will have this nasty stuff in your N2O.

Since 22- 24 liters of N2O are produced from 80g of AN (AN costs only 2,50€ per kg for me), this method is very economic in terms of used chemicals.

However, the problem is not the generation of the N2O, but rather its purification.

The gas contains appreciable quantities of NO2 and NO which must be completely removed.

By bubbling the gas through NaOH soln, the NO2 can be removed. Several washing flasks have to be used in series to remove all of it.

However, NO is not removed this way!
NO doesn't react with bases.
Mixing the N2O with a little air doesn't oxidise all of the NO fast enough because of the great dilution.

I have read that oxidisers like permanganate, dichromate and hypochlorite can oxidise it to NO2.
Permanganate oxidises it quantitatively and this is used as a method of analyzing NO in gas mixes.

So I should probably use a washing boottle with NaOH first, then one with permanganate and then several with NaOH.

How can I find out if the gas still contains NO?
Maybe by smelling it?
I even smell NO2 in car exhausts on the street in the morning when going to school, so I should theoretically be able to detect it.

About storing it:
N2O is surprisingly soluble in water, 1l water will dissolve 1,5l of N2O at 0°C.
When a saturated solution of N2O in water is cooled to its freezing point, crystals with the formula N2O*6H2O crystallize out. They are stable below 0°C and decompose to water and the gas on warming.
This method will of course remove ALL of the NO2, since NO2 reacts with the water rapidly once dissolved.
And NO is quite insoluble in water, 1l dissolves only 70ml.
If the water contains some sodium hypochlorite (maybe hydrogen peroxide works, too?) the NO would be oxidised to nitric acid and on warming the N2O-hydrate crystals, we would get very pure N2O.

I will investigate this in the next few weeks.
I never worked with gas hydrates before, so this will be interesting.

garage chemist - 19-1-2005 at 14:14

I just got some pure AN and started experimenting.
I heated 20g in the described apparatus, it formed a crystal clear melt and decomposed steadily without getting violent. The gas was bubbled through NaOH in a selfmade washing
bottle and smelled totally clean and sweetish, not the slightest hint of NO2.
I filled it into a plastic freezer bag tied to a glass pipe, and when the bag was full, the pipe to the bag was disconnected from the washing bottle.

I smelled the gas, and, sure enough, it strongly smelled of NO2. :mad:

The NO in the crude N2O had reacted with residual air in the plastic bag.

I really need to find a method of absorbing NO!

N2O is highly flammable

miseryland - 19-1-2005 at 15:06

basic rule, most stuff burns once it reaches a temperature or other condition,
for flurine mere contact with oxygen (not good) for nitrous oxide relatively high temperatures, dont believe me, throw a nos cylinder for nos crackers into a bonfire, oh yes stand behind somethin solid ie a brick wall, schrapnel is not kind to human flesh, and maybe a fire extinguisher just in case

Theoretic - 20-1-2005 at 14:28

"N2O is highly flammable

basic rule, most stuff burns once it reaches a temperature or other condition,"

Basic rule, stuff burns if there's an oxidizer to react with. N2O itself is an oxidizer, so it can't burn.

"for flurine mere contact with oxygen (not good)"

When fluorine gets into mere contact with oxygen, nothing happens. They don't react just like that, and for good reason: all of their compounds are endothermic.

"for nitrous oxide relatively high temperatures, dont believe me, throw a nos cylinder for nos crackers into a bonfire, oh yes stand behind somethin solid ie a brick wall, schrapnel is not kind to human flesh, and maybe a fire extinguisher just in case"

Any gas, when confined in a small container and heated, will blow the container and make shrapnel. N2O can additionally exothermically decompose (sometimes explosively, but it's not BURNING!) into N2 and O2, above 500 C I think.

removing NO

Polverone - 27-1-2005 at 20:55

The soon-to-be-released DLI book <i>Industrial Nitrogen Compounds and Explosives</i> indicates that NO can be removed from NH4NO3 decomposition products by passing the gas formed through a solution of ferrous sulfate.

garage chemist - 28-1-2005 at 03:25

A-ha! Thanks for the info! I'll try that out soon.

I once saw something similar in a video, where colourless NO (diluted with argon) was bubbled through some iron- salt solution and it formed an intensely blue "pentaaqua-nitrosyleisen" complex.
I wondered if this could be used to absorb NO.

Ferrous sulfate is FeSO4, right?
Can I make it by dissolving iron nails in dilute H2SO4?

How concentrated does the FeSO4- solution have to be?
Does it have to be acidic, or neutral?

Polverone - 28-1-2005 at 11:41

Yes, you can make FeSO4 with nails in diluted H2SO4; keep it at least somewhat protected from air of course. I think the scrubbing solution can be acidic or neutral. In one of the arrangements described, NH4NO3 decomposition gases were bubbled through aqueous FeSO4 solution (specifics unspecified) and later dried/cleaned again by passing through a slurry of FeSO4 in conc. H2SO4. NO2 and CO2 were removed by passing through an aqueous mixture of KOH and Ca(OH)2. I presume that CO2 was a minor impurity.

Mumbles - 28-1-2005 at 17:18

For making ferrous sulfate it is best to use an excess of iron, otherwise the acid will start oxidising it to ferric. Also do it outside as there is SO2 given off. Not pleasant when you just let it react on it's own in the basement. Crashing out with alcohol may be the way to go if you want to isolate it.

Mindchemist - 5-4-2011 at 19:16

You could also try the reaction of sodium nitrite and hydroxylammonium chloride to make nitrous oxide:

atomicfire - 6-4-2011 at 07:29

Quote: Originally posted by The_Davster  
Heres a pretty easy DIY method;[/url]

I know that guy! He was in graduate school when I was an undergrad. Small world.

AndersHoveland - 3-6-2013 at 09:22

It might not be the most practical preparation, but Nicolai Lehnert at the University of Michigan discovered a di-iron complex that can catalyze the reaction of nitric oxide with nitrogen gas to nitrous oxide at room temperature