Sciencemadness Discussion Board - Wich salt makes the most attractive nitration mix with H2SO4?

Wich salt makes the most attractive nitration mix with H2SO4?

dangerous amateur - 5-8-2013 at 03:41

Hi,

i don't have much HNO3 in find it hard to get some, on the other hand H2SO4 is easy to get in 98%.

Now if you had the choice for potassium, sodium or calcium nitrate to fill your stockpile with - what would you choose to make nitrations with?

Drying before use is not a problem for me.

Dany - 5-8-2013 at 03:56

hello,

theoretically all salts that contain nitrate can be used for nitration ammonium, sodium, potassium and calcium nitrate because they all generate nitric acid in situ. what is not desirable in calcium nitrate is that CaSO4 formed in situ is poorly soluble in water wich make your solution very viscous and close to a slurry. so potassium and sodium nitrate are the best choice.

Dany.

THIS IS A U.S PATENT DEALING WITH THE SYNTHESIS OF NITRATE ESTER USING SALTS AS A NITRATE SOURCE. AMMONIUM NITRATE IS USED AS EXAMPLE.

P.S READ CAREFULLY BEFOR ATTEMPTING ANY SYNTHESIS ! EXPLOSIVE AND HIGH ENERGY MATERIALS ARE NOT TOYS!

[Edited on 5-8-2013 by Dany]

Attachment: Methods of producing nitrate ester.pdf (130kB)
This file has been downloaded 853 times

[Edited on 5-8-2013 by Dany]

[Edited on 5-8-2013 by Dany]

dangerous amateur - 5-8-2013 at 05:11

Thanks, but basically I'm aware of that.

I forgot that CaSO4 is insoluble. That means it's unsuitable, causing additional trouble in filtering the unsoluble esters out.

But let's compare ammonium, sodium and potassium nitrate.

I often read that apart from the stoichiometrical advantage, more NO3 per weight, people get better yields with AN than with an stoichiometrical aequivalent of KNO3...

AN seems to be better than KNO3. How would NaNO3 compare with these two?

[Edited on 5-8-2013 by dangerous amateur]

Dany - 5-8-2013 at 05:16

since sodium and potassium are to alkali matals close to each other i think that NaNO3 and KNO3 will perform similarly.
another imporatnt thing, it is wrong to say that KNO3 is better than NaNO3 or vice-versa because the performance of each one depend on the reaction condition and on organic substrat that will undergo nitration. so the nitrating salt is not the only factor that determine the yield of reactions.

Dany.

[Edited on 5-8-2013 by Dany]

TheChemiKid - 5-8-2013 at 07:45

Ammonium Sulfate is the most soluble of Potassium, Sodium, and Ammonium Sulfate salts. Next is Sodium Sulfate Pentahydrate.

Fantasma4500 - 5-8-2013 at 08:31

it depends on what you want to nitrate, fx. for ETN some report higher yield with KNO3, repeating the synthesis by the same ways
while others say its shit

there is difference, not sure how to define it, just test it with HNO3, NH4NO3 and KNO3 yourself
obviously 99% HNO3 would be the best, or well for the synthesis i know of it would be

also, TheChemiKid, you might want to consider that the sulfate takes up water, so it might not be that good, as there wont be any water to keep it 'dissolved' in
the same does CaSO4

papaya - 5-8-2013 at 10:43

Quote: Originally posted by Antiswat

also, TheChemiKid, you might want to consider that the sulfate takes up water, so it might not be that good, as there wont be any water to keep it 'dissolved' in
the same does CaSO4

Isn't it good that sulfate takes water beneficially shifting equilibrium to the ester formation ?

caterpillar - 5-8-2013 at 12:19

You, boys, are wrong about Ca(NO3)2. It has its own advantages. I tried all of aforementioned salts. I used KNO3 for TNP preparation and I think that it is the best choice for this particular compound. I got a runaway reaction, when I tired to use NH4NO3 instead. It was a mild reaction, but I got a foam with red bubbles and had to stop process. Ca(NO3)2 is the best choice for NC or NG. There are some simple tricks with it. You have to delete all water from it and then smash this mass to small pieces, but not to dust. 1-3 mm in size. Then put it into H2SO4- I used 92-94 % acid. Wait for a day and night. some times you have to turn a bottle with mixture bottom up- pieces of Ca(NO3)2 must go down through acid. Then you may decant the upper layer. Yeah, you'll loose some mixed acid with CaSO4, because it forms very small crystals. But most likely it extracts some water from acid and therefore increases concentration of resulting mixed acid.

papaya - 5-8-2013 at 12:22

Where you all get Ca nitrate?

Metacelsus - 5-8-2013 at 13:25

Hydroponics stores sell it. It's used to provide calcium and nitrogen to plants (big surprise!). Alternatively, one could react nitric acid with calcium carbonate/hydroxide/oxide, but if you already have HNO3, what's the point of that?

Rosco Bodine - 5-8-2013 at 22:54

This is actually a very interesting topic because there is a different nitrating activity by different nitrates in combination with sulfuric acid as a general trend
or for nitration of a particular material a specific nitrate may have better activity than a different nitrate. Exactly why this is true I am not sure. Urbanski has charted what is the general progression of activity for the nitrates, but it is not written in stone that activity progression holds true for every material to be nitrated. Urbanski does not elaborate about how the tests were done or what was the material being nitrated for his tests or is the results are even actually his tests or information from others. One thing that would be a factor is that some nitrates produce an acid sulfate byproduct and other nitrates produce a normal sulfate byproduct, which effectively doubles the amount of nitric acid produced. Another factor is that the byproduct sulfate may have dehydrating properties which can benefit the nitration. Some nitrates are nearly impossible to be found alone in anhydrous form, but can be melted in mixture with another nitrate and will form an anhydrous double salt or eutectic which could provide a useful mixed nitrate for use as a nitrating salt when mixed with sulfuric acid.
There is nothing i have found in the literature about the use of such mixed nitrate salt compositions for nitrations but I have posted everything I could find about these mixed nitrate systems. There was also posted a patent reference to an ammonium nitrate mixed with sodium nitrate extreme low water content melt which might be useful in a high temperature nitration scheme for nitration of aromatic compounds which require the higher nitration temperatures. There are several low water content systems where one nitrate greatly increases solubility in the presence of another different nitrate and enables the formation of a supersaturated brine having water content in the single digit percentage range, even down to 1% water content at elevated temperatures where the solution is almost but not quite a eutectic melt. Many novel nitration schemes could probably be devised to make use of such mixtures. It would likely be purely experimental since there seems to be no existing literature, or at least none that I have found to provide guidance.

caterpillar - 6-8-2013 at 01:55

Ca(NO3)2 can be prepared from AN and Ca(OH)2. I wrote about my own experiments. The first one was rather stupid- I put some phenol into a vessel, then added KNO3 and H2SO4. The last one ignited phenol. But later I understood, how nitrates can replace nitric acid in mixed acid. I think, that AN + H2SO4 would be the best for preparation of urea nitrate for example- this reaction requires low temperature and therefore runaway hardly will be possible. As I wrote, KNO3 is the best for preparation of TNP. I got very few nitrogen oxides during this process. But at hi temperature AN + H2SO4 might react (it is my proposition, but I can only repeat- I got red foam once and had to stop nitration). Dear Ledgard recommends KNO3 for preparation of trinitronaphtalene.

Rosco Bodine - 6-8-2013 at 02:02

NaNO3 works better than KNO3 for TNP in my experience. However both will work.

Gargamel - 6-8-2013 at 04:23

This is interesting.
Wouldn't non water soluble sulfates like barium or calcium sulfate actually be a great advantage?

Recently I was very angry because I found such stuff almost impossible to filter, a real pita. So I just decanted it using a long measuring cylinder.

The only problem is it takes days.

In theory one should get a totally liquid nitration mix, that can be stirred with a magnetic stirrer - a big advantage.

Dany - 6-8-2013 at 04:45

Gargamel,

it is a bad idea to leave your nitrated organic compound in contact with the nitrating acid mixture for days. Indeed, the situation is is more dangerous when synthesizing nitrate ester which hydrolyses upon standing in acid mixture which probably cause decomposition or detonation in some case. I suggest to nitrate with other salts like sodium, potassium or ammonium nitrate and then do an extraction of your aqueous phase with Ethyl acetate ,dichloromethane or ether depending on the solubility of your organic compound.

Dany.

Motherload - 6-8-2013 at 05:46

Dany I don't believe he was leaving the organic compound in the mix for days ..... Rather the Nitrate H2SO4 mix so he could decant off majority of the HNO3.
Like I posted here
http://www.sciencemadness.org/talk/viewthread.php?tid=20638
The second half of my post.

Rosco Bodine - 6-8-2013 at 06:25

It is the nitrates which form water soluble sulfates or acid sulfates that are of interest. There is a mixed composition of KNO3 and Mg(NO3)2 which will dehydrate completely on heating, more easily in a vacuum oven and that mixture would seem interesting. Likewise there is a mixture of NH4NO3 and Mg(NO3)2 which forms an anhydrous melt and there are several others. The nitrates that form insoluble sulfate byproducts are going to cause problems with filtration and isolation particularly if the insoluble byproduct exceeds a certain small percentage but as a minor proportion of the mixture it might be tolerable.
Anyway the mixed nitrates scheme is the method which has promise for eliminating the water of hydration that may be impossible otherwise to eliminate for nitrates like Mg(NO3)2 which will otherwise hold their water of hydration so tenaciously that they decompose to the oxide when heated to try to eliminate the crystal water completely. Of all the nitrates the Mg(NO3)2 is of particular interest, either its lower hydrate used alone or its use in a mixed nitrate scheme where its hydration level approaches nearer to zero.

Gargamel - 6-8-2013 at 07:20

Quote:

it is a bad idea to leave your nitrated organic compound in contact with the nitrating acid mixture for days

It was not a nitration mixture. It was just where I got the idea.

Quote:

Rather the Nitrate H2SO4 mix so he could decant off majority of the HNO3.

Exactly.

Caterpillars method sounds very interesting to me.

I never thought that stuff that's not water soluble is used as a desiccant

I know of course that plaster of paris draws water over time and gets useless.

How easily can Calcium nitrate be dehydrated - just heating in a pan like AN?

caterpillar - 6-8-2013 at 13:18

Quote: Originally posted by Gargamel

Caterpillars method sounds very interesting to me.

I never thought that stuff that's not water soluble is used as a desiccant

I know of course that plaster of paris draws water over time and gets useless.

How easily can Calcium nitrate be dehydrated - just heating in a pan like AN?

Try it. It is very simple. I put Ca(NO3)2*4H2O onto a frying pan in my kitchen. Salt boils, than becomes a solid mass. It looses water at 130-150 Celsius. Overheating is impossible- destruction of dry Ca(NO3)2 requires hi temperature. I read once about preparation of superphosfate- this fertilizer was prepared in the similar way from absolutely insoluble Ca3(PO4)2. Smash dry calcium nitrate to pieces. Assume, you want to get mixed acid with 40% of HNO3 and 60 % of H2SO4- usual mix. Assume, that calcium nitrate will completely converted to sulphate- this proposition is not far from reality. Thus you may easy calculate, how much of dry calcium nitrate is to be put into 100 gr of sulfur acid. One day and night, and do not forget to turn reaction vessel bottom up some times. The upper layer will be clear. If you have a vacuum filter, you may extract some additional mixed acid from sediment after you'll have decanted the upper layer.

[<a href="u2u.php?action=send&username=bfesser">bfesser</a>: fixed BBCode]

[Edited on 6.8.13 by bfesser]

Motherload - 6-8-2013 at 19:42

Sir Bodine.
I was thinking of this method of making Anhydrous Mg(NO3)2.
Does it seem feasible ?
http://www.sciencemadness.org/talk/viewthread.php?tid=23632
Last post.

Thanks

Rosco Bodine - 7-8-2013 at 15:26

No it doesn't look very promising to me.

Rosco Bodine - 9-8-2013 at 08:57

On this page linked below is attached the file from Urbanski regarding the nitrating activity of a few nitrates

http://www.sciencemadness.org/talk/viewthread.php?tid=4457&a...

papaya - 9-8-2013 at 09:31

Something from Urbanski v4.
<img src="http://www.freeimagehosting.net/newuploads/18rpm.png" alt="Free Web Proxy">
I won't say I completely understand what it is written there, just that the kind of bisulfate [forming in reaction] can affect nitration.

[Edited on 9-8-2013 by papaya]

[Edited on 9-8-2013 by papaya]

[Edited on 9-8-2013 by papaya]

Rosco Bodine - 9-8-2013 at 11:16

To a very limited extent of a small low percentage amount of water, the presence of water in a very limited and narrow range can be beneficial to nitrations and this has been documented for TNT and for nitrocellulose and
probably applies to many other nitrations where the water content has not been studied and charted on a nitration process graph along with optimum temperatures and times for reaction. The presence of various salts has also been observed to have a favorable effect on nitration reaction rate and acid utilization efficiency. These process refinements are certainly applicable to small scale synthesis which is in many cases exactly how these enhancements and process refinements were discovered.

papaya - 9-8-2013 at 13:46

I have a naive question I want to be answered - everybody has heard about nitric acid+ Ac2O nitrating mixture that used in situation where sulfuric acid is an impossible (RDX,etc), also I've heard something on P2O5 + nitric acid usage, so is there any chance that nitric acid + B2O3 is workable, does the mixed anhydride of H3BO3 and HNO3 even exist? Wikipedia says boric acid will decompose at 300°C to give B2O3, which is easy if the rest is true.

Dany - 11-8-2013 at 14:22

Hello Papaya,

Aryl boronic acid can be used with alkylnitrite for aromatic nitration of electron rich substrate. Electron poor substrates need the addition of Boric acid to accomplish the nitration

see Sheme 18 of the following paper on aromatic nitration:

Attachment: Recent advances in the synthesis of aromatic nitro compounds.pdf (734kB)
This file has been downloaded 863 times

Fantasma4500 - 28-8-2013 at 10:24

Quote: Originally posted by caterpillar

You, boys, are wrong about Ca(NO3)2. It has its own advantages. I tried all of aforementioned salts. I used KNO3 for TNP preparation and I think that it is the best choice for this particular compound. I got a runaway reaction, when I tired to use NH4NO3 instead. It was a mild reaction, but I got a foam with red bubbles and had to stop process. Ca(NO3)2 is the best choice for NC or NG. There are some simple tricks with it. You have to delete all water from it and then smash this mass to small pieces, but not to dust. 1-3 mm in size. Then put it into H2SO4- I used 92-94 % acid. Wait for a day and night. some times you have to turn a bottle with mixture bottom up- pieces of Ca(NO3)2 must go down through acid. Then you may decant the upper layer. Yeah, you'll loose some mixed acid with CaSO4, because it forms very small crystals. But most likely it extracts some water from acid and therefore increases concentration of resulting mixed acid.

would this mean, that you would be able to make pretty well 99% HNO3 somewhat, without any CaSO4 being suspensed in the solution?? thats very interesting, i didnt consider that the H2SO4 / Ca(NO3)2 mix would create runoff when i filtered it through paper. anyhow i still stick to the idea that it will fully work if using a nice big sheet of NC for filtering it with (bought NC perhaps, or extracted from fireworks?)

caterpillar - 28-8-2013 at 14:16

The upper layer was transparent, therefore there was no CaSO4, floating in. You may use glass material or asbestos for filtering after decantation of the upper layer. I do not think, that in that way one may get pure HNO3- same problem with floating CaSO4. I made usual mix- 60% H2SO4 and 40% HNO3. Therefore, initially I had large enough amount of liquid and pieces of Ca(NO3)2 was completely covered with sulfur acid. If one take smaller amount of H2SO4, wanting to get only HNO3 plus gypsum, he surely will get mess of liquid and small crystals and no upper layer to decant it. But may be even in such case liquid could be extracted, using vacuum filtering. I never tried- do it for yourself.