Hexogen Troubles

[simply RED]

I found 1 liter nitric acid which was labeled to be 100% .
It was not different from the distilled NA.
The first thing i tried with it was RDX (to see if the acid works).
Here the problems started.

I cooled the acid to zero degrees celsius and added slowly some hexamine
(1 gram per 10ml). Hissing noise was heared and red smoke was seen.
After all hexamine was added i rised the temperature , when it reached 10 degrees celsius, runaway happened !!!!
The next 3 attempts i diluted the aicd to 95 % and the same thing happened
the 5th attempt i used hexmine dinitrate with the same resault.....

I never ever had any runaway with hexogen....
Do you have explanation why this happened.
Any good way to turn red acid to white will be wellcomed as the process with urea does not work at all...

[simply RED]

I found 1 liter nitric acid which was labeled to be 100% .
It was not different from the distilled NA.
The first thing i tried with it was RDX (to see if the acid works).
Here the problems started.

I cooled the acid to zero degrees celsius and added slowly some hexamine
(1 gram per 10ml). Hissing noise was heared and red smoke was seen.
After all hexamine was added i rised the temperature , when it reached 10 degrees celsius, runaway happened !!!!
The next 3 attempts i diluted the aicd to 95 % and the same thing happened
the 5th attempt i used hexmine dinitrate with the same resault.....

I never ever had any runaway with hexogen....
Do you have explanation why this happened.
Any good way to turn red acid to white will be wellcomed as the process with urea does not work at all...

[simply RED]

I found 1 liter nitric acid which was labeled to be 100% .
It was not different from the distilled NA.
The first thing i tried with it was RDX (to see if the acid works).
Here the problems started.

I cooled the acid to zero degrees celsius and added slowly some hexamine
(1 gram per 10ml). Hissing noise was heared and red smoke was seen.
After all hexamine was added i rised the temperature , when it reached 10 degrees celsius, runaway happened !!!!
The next 3 attempts i diluted the aicd to 95 % and the same thing happened
the 5th attempt i used hexmine dinitrate with the same resault.....

I never ever had any runaway with hexogen....
Do you have explanation why this happened.
Any good way to turn red acid to white will be wellcomed as the process with urea does not work at all...

[Microtek]

To remove NOx, heat the acid to 50 C and bubble dry air ( CaCl2 tube ) through until colourless.

[Microtek]

To remove NOx, heat the acid to 50 C and bubble dry air ( CaCl2 tube ) through until colourless.

[Microtek]

To remove NOx, heat the acid to 50 C and bubble dry air ( CaCl2 tube ) through until colourless.

[simply RED]

Thanks for the advise! I will try it as soon as possible.
by the way: What vessel do you use to carry out the process and doesn't the acid evaporate during it?

[simply RED]

Thanks for the advise! I will try it as soon as possible.
by the way: What vessel do you use to carry out the process and doesn't the acid evaporate during it?

[simply RED]

Thanks for the advise! I will try it as soon as possible.
by the way: What vessel do you use to carry out the process and doesn't the acid evaporate during it?

[aikon]

Another method to get rid of the NO2 contaminats is to add a little urea to the acid and warm it a little bit. If the color doesn't vanish you could try the CaCl2 method.

[aikon]

Another method to get rid of the NO2 contaminats is to add a little urea to the acid and warm it a little bit. If the color doesn't vanish you could try the CaCl2 method.

[aikon]

Another method to get rid of the NO2 contaminats is to add a little urea to the acid and warm it a little bit. If the color doesn't vanish you could try the CaCl2 method.

[Dave Angel]

Depending on your equipment you could put the acid in a pyrex jug with pouring spout and place a pyrex bowl on top of it, filled with ice slush or antifreeze/water (a 50:50 mixture can go down to about -20C as liquid). The spout gives you room to fit the gas bubbler of choice into the acid; the bowl condensing evaporating acid.

Currently, I don't even bother condensing the evaporating acid, though I do seem to lose a few mls. To rectify this I have in mind the use of a three necked flask, one neck stoppered, a sintered gas bubbler (from a Drechsel) in another and a reflux condensor in the main socket. The only limitation of this being the need for a litre of acid before it will work well, as the flask is 2L.

Check out this thread for more details on purging NOx:

http://www.roguesci.org/theforum/showthread.php?t=1902

Nice one on finding the litre of acid by the way!

[Dave Angel]

Depending on your equipment you could put the acid in a pyrex jug with pouring spout and place a pyrex bowl on top of it, filled with ice slush or antifreeze/water (a 50:50 mixture can go down to about -20C as liquid). The spout gives you room to fit the gas bubbler of choice into the acid; the bowl condensing evaporating acid.

Currently, I don't even bother condensing the evaporating acid, though I do seem to lose a few mls. To rectify this I have in mind the use of a three necked flask, one neck stoppered, a sintered gas bubbler (from a Drechsel) in another and a reflux condensor in the main socket. The only limitation of this being the need for a litre of acid before it will work well, as the flask is 2L.

Check out this thread for more details on purging NOx:

http://www.roguesci.org/theforum/showthread.php?t=1902

Nice one on finding the litre of acid by the way!

[Dave Angel]

Depending on your equipment you could put the acid in a pyrex jug with pouring spout and place a pyrex bowl on top of it, filled with ice slush or antifreeze/water (a 50:50 mixture can go down to about -20C as liquid). The spout gives you room to fit the gas bubbler of choice into the acid; the bowl condensing evaporating acid.

Currently, I don't even bother condensing the evaporating acid, though I do seem to lose a few mls. To rectify this I have in mind the use of a three necked flask, one neck stoppered, a sintered gas bubbler (from a Drechsel) in another and a reflux condensor in the main socket. The only limitation of this being the need for a litre of acid before it will work well, as the flask is 2L.

Check out this thread for more details on purging NOx:

http://www.roguesci.org/theforum/showthread.php?t=1902

Nice one on finding the litre of acid by the way!

[simply RED]

10x!
Combining these methods (air and urea) i got acid good enough for
nitrocellulose and other esters.
The yield of RDX is still half the calculated.
The interesting fact is that the acid needed to be diluted first to 99-95% and then processed. Direct mixing with urea caused even more NOx and heat!
Direct mixing with urea solution in water caused runaway, water suspension of hexamine dinitrate caused runaway too.
100% acid that is at least 5 years old is quite different from the fresh distilled 93-95%.
Next time i will try urea nitrate method (somebody mentioned the idea in the purging thread). You could mix very much urea nitrate to the acid and still have concentrated one.

[simply RED]

10x!
Combining these methods (air and urea) i got acid good enough for
nitrocellulose and other esters.
The yield of RDX is still half the calculated.
The interesting fact is that the acid needed to be diluted first to 99-95% and then processed. Direct mixing with urea caused even more NOx and heat!
Direct mixing with urea solution in water caused runaway, water suspension of hexamine dinitrate caused runaway too.
100% acid that is at least 5 years old is quite different from the fresh distilled 93-95%.
Next time i will try urea nitrate method (somebody mentioned the idea in the purging thread). You could mix very much urea nitrate to the acid and still have concentrated one.

[simply RED]

10x!
Combining these methods (air and urea) i got acid good enough for
nitrocellulose and other esters.
The yield of RDX is still half the calculated.
The interesting fact is that the acid needed to be diluted first to 99-95% and then processed. Direct mixing with urea caused even more NOx and heat!
Direct mixing with urea solution in water caused runaway, water suspension of hexamine dinitrate caused runaway too.
100% acid that is at least 5 years old is quite different from the fresh distilled 93-95%.
Next time i will try urea nitrate method (somebody mentioned the idea in the purging thread). You could mix very much urea nitrate to the acid and still have concentrated one.

[Microtek]

Whenever I produce fuming HNO3, I do it at atmosphere pressure so I get quite a lot of NOx if I'm in a hurry. The cool acid may appear reasonably white, so it can be difficult to see when enough NOx has been remved.
I then heat up the collected HNO3 to ca 50 C ( the goal is not to make the NOx more visible, but rather to raise the partial pressure of NOx over the HNO3 ) and bubble dry air through it.
I do the operation in a tall glass vessel to minimize the amount of HNO3 that escapes, but of course there is a little evaporation. I usually need to maintain the airstream for about 2-5 minutes with a small aquarium air pump.
In this way the acid becomes as colourless as water, and ends up with a concentration of more than 99 % ( if the distillation was done a little carefully to avoid too much decomposition ).
The loss of acid due to evaporation during the purging step is about 1-2 % but this could likely be improved by optimizing the airflow.
And by the way, those of you that measure the concentration of your HNO3 by density measurements, note that NOx dissolved in the acid makes it much more dense; in a typical slow distillation with moderate NOx evolution, the acid can appear to be ca. 95% before purging the NOx when in reality it is only 80-85 %.

[Microtek]

Whenever I produce fuming HNO3, I do it at atmosphere pressure so I get quite a lot of NOx if I'm in a hurry. The cool acid may appear reasonably white, so it can be difficult to see when enough NOx has been remved.
I then heat up the collected HNO3 to ca 50 C ( the goal is not to make the NOx more visible, but rather to raise the partial pressure of NOx over the HNO3 ) and bubble dry air through it.
I do the operation in a tall glass vessel to minimize the amount of HNO3 that escapes, but of course there is a little evaporation. I usually need to maintain the airstream for about 2-5 minutes with a small aquarium air pump.
In this way the acid becomes as colourless as water, and ends up with a concentration of more than 99 % ( if the distillation was done a little carefully to avoid too much decomposition ).
The loss of acid due to evaporation during the purging step is about 1-2 % but this could likely be improved by optimizing the airflow.
And by the way, those of you that measure the concentration of your HNO3 by density measurements, note that NOx dissolved in the acid makes it much more dense; in a typical slow distillation with moderate NOx evolution, the acid can appear to be ca. 95% before purging the NOx when in reality it is only 80-85 %.

[Microtek]

Whenever I produce fuming HNO3, I do it at atmosphere pressure so I get quite a lot of NOx if I'm in a hurry. The cool acid may appear reasonably white, so it can be difficult to see when enough NOx has been remved.
I then heat up the collected HNO3 to ca 50 C ( the goal is not to make the NOx more visible, but rather to raise the partial pressure of NOx over the HNO3 ) and bubble dry air through it.
I do the operation in a tall glass vessel to minimize the amount of HNO3 that escapes, but of course there is a little evaporation. I usually need to maintain the airstream for about 2-5 minutes with a small aquarium air pump.
In this way the acid becomes as colourless as water, and ends up with a concentration of more than 99 % ( if the distillation was done a little carefully to avoid too much decomposition ).
The loss of acid due to evaporation during the purging step is about 1-2 % but this could likely be improved by optimizing the airflow.
And by the way, those of you that measure the concentration of your HNO3 by density measurements, note that NOx dissolved in the acid makes it much more dense; in a typical slow distillation with moderate NOx evolution, the acid can appear to be ca. 95% before purging the NOx when in reality it is only 80-85 %.

[simply RED]

I bought a small oxygen bottle with good regulating vent.
No electric apparature and no drying needed. Hexogen yield slightly under the theoretical . (about 3 grams from 10 ml with hexamine dinitrate method)
Anyway using oxygen is not a cheaper alternative.

[simply RED]

I bought a small oxygen bottle with good regulating vent.
No electric apparature and no drying needed. Hexogen yield slightly under the theoretical . (about 3 grams from 10 ml with hexamine dinitrate method)
Anyway using oxygen is not a cheaper alternative.

[simply RED]

I bought a small oxygen bottle with good regulating vent.
No electric apparature and no drying needed. Hexogen yield slightly under the theoretical . (about 3 grams from 10 ml with hexamine dinitrate method)
Anyway using oxygen is not a cheaper alternative.

[mongo blongo]

Simply RED: Was that using Urea Nitrate or just pure oxygen?

[mongo blongo]

Simply RED: Was that using Urea Nitrate or just pure oxygen?

[mongo blongo]

Simply RED: Was that using Urea Nitrate or just pure oxygen?

[simply RED]

This was done using pure oxygen from oxygen bottle and bubbling it until the acid
decolorises both at 40 degrees or without heating. The gas was bubbled through medicine needle from glucose system.
I haven't tried urea nitrate method till now, just done the calculations.

p.s. The roommate come and I won't be able to do any research long time ahead which is quite depressing...

[simply RED]

This was done using pure oxygen from oxygen bottle and bubbling it until the acid
decolorises both at 40 degrees or without heating. The gas was bubbled through medicine needle from glucose system.
I haven't tried urea nitrate method till now, just done the calculations.

p.s. The roommate come and I won't be able to do any research long time ahead which is quite depressing...

[simply RED]

This was done using pure oxygen from oxygen bottle and bubbling it until the acid
decolorises both at 40 degrees or without heating. The gas was bubbled through medicine needle from glucose system.
I haven't tried urea nitrate method till now, just done the calculations.

p.s. The roommate come and I won't be able to do any research long time ahead which is quite depressing...

[Oktogen]

I'm wondering if one can use CO2 instead of oxygen, I've got plenty of it, 6kg bootle. :D Maybe oxidation of impurities in CO2 will occour and NA will decompose to NO2 :confused: ,but using CO2 has the advantage that CO2 costs 6dollars per 6kg :D :D :cool:

[Oktogen]

I'm wondering if one can use CO2 instead of oxygen, I've got plenty of it, 6kg bootle. :D Maybe oxidation of impurities in CO2 will occour and NA will decompose to NO2 :confused: ,but using CO2 has the advantage that CO2 costs 6dollars per 6kg :D :D :cool:

[Oktogen]

I'm wondering if one can use CO2 instead of oxygen, I've got plenty of it, 6kg bootle. :D Maybe oxidation of impurities in CO2 will occour and NA will decompose to NO2 :confused: ,but using CO2 has the advantage that CO2 costs 6dollars per 6kg :D :D :cool:

[simply RED]

A friend of mine here found a lab manual that uses CO2.
The manual states CO2 is the best to use.

[simply RED]

A friend of mine here found a lab manual that uses CO2.
The manual states CO2 is the best to use.

[simply RED]

A friend of mine here found a lab manual that uses CO2.
The manual states CO2 is the best to use.

[Boomer]

Yes, CO2, N2, O2, dry air... all work, they just blow out the NO2 which is more volatile than the HNO3 (somewhat like steam distillation). There is no further oxidation of the nitrous with the O2 unless there is lots of pressure.

In industry, they blow out the nitrous with nitric vapour, which blows upwards through a tower where the acid drops down. The liquid HNO3 condenses the HNO3 fumes while the fumes clean the acid!

[Boomer]

Yes, CO2, N2, O2, dry air... all work, they just blow out the NO2 which is more volatile than the HNO3 (somewhat like steam distillation). There is no further oxidation of the nitrous with the O2 unless there is lots of pressure.

In industry, they blow out the nitrous with nitric vapour, which blows upwards through a tower where the acid drops down. The liquid HNO3 condenses the HNO3 fumes while the fumes clean the acid!

[Boomer]

Yes, CO2, N2, O2, dry air... all work, they just blow out the NO2 which is more volatile than the HNO3 (somewhat like steam distillation). There is no further oxidation of the nitrous with the O2 unless there is lots of pressure.

In industry, they blow out the nitrous with nitric vapour, which blows upwards through a tower where the acid drops down. The liquid HNO3 condenses the HNO3 fumes while the fumes clean the acid!

[Diabolique]

NOx is the biggest cause of loss of product, according to LANL and LLNL reports I've read. Run-away reactions also are a problem according to Urbanski. (In sulfuric acid, SO2 can be another major run-away problem when nitrating aromatics like toluene).

A suggestion for an aerator/dehydrator for removing NOx from nitric acid. Take a jar with a screw-type lid, and solder two short brass tubes to it, obe protruding less than 1 cm, the other reaching to the bottom of the jar. Fill the jar with CaCl2 and push the long tube thru it to the bottom, and screw the lid in place. Use an aquarium air pump to blow air into the short tube, and a plastic tube to a glass tube in the acid. You will need some sort of volume regulator to keep from splashing concentrated acid around.

This should also be useful for aggitating nitration mixtures, but nitrogen may be needed for some.

The labs have done a little work on using KNO3 and sulfuric acid for nitration. It is easy to get sulfuric acid to 95% or better by boiling it (a LOT hotter than boiling water), so a concentrated acid mixture results. I wonder what happens if one uses anhydrous calcium nitrate? CaSO4 results, which is hydrophilic. Would it scavenge water from the nitrating acids, of would the acids hold onto the water? I never heard of that being tried, and I am no longer able to stand, let alone work safely in the lab.

[Cindor]

What about acetylene ? can be used to get NO2 away from HNO3?
Is easy to produce it in a lab (CaC2 + 2 H2O --- Ca(OH)2 + C2H2), and very cheap.

[nbk2000]

I believe that passing acetylene through nitric acid forms TeNM, a VERY powerful, yet insanely sensitive, explosive. Not the sort of thing you'd want as a side-product in a very stable explosive like RDX.

[Cindor]

Yes, that with 95+% Nitric Acid... but what about 60-70% ? Would that produce TriNitroMethane and then TetraNitroMethane or just get de NO2 away ?
I'm not trying to make TeNM... just trying to get out the NO2 from my Nitric Acid

[nbk2000]

Removal of NOx has been discussed countless times.

UTFSE. :)

As for what percentage of HNO3 is required for making TeNM, I don't know off-hand. Probably a very high percentage, like 95%.

[megalomania]

Ahem, http://roguesci.org/megalomania/explo/tetranitromethane.html

Nitric acid needed is 100%

It is a dangerous explosive, but more so it is dangerously toxic; a potential CW candidate.

[simply RED]

Is anhydridous calcium nitrate possible to be made at home? I've heared the water complex will rather decompose (when heated) than dehydrate.

CaSO4 is moderately soluble (not insoluble like PbSO4) in concentrated
HNO3/H2SO4 - which has been discussed many times.

[Bradt]

My opinion is, the synthesis of hexogen is sensitive. You have to control your temperature. Nitric acid +96% is required and +99% white nitric acid is ideal. It happens the yield is more than low if you use nitric acid which is more dillute.