krazypunk50
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RDX KA Method (big big problem)
A few days ago I had a go at the KA method of producing rdx. the synthesis went as follows:
Dissolve 50 grams of hexamine (see Kitchen Improvised Plastic Explosives) in 150 ml. of water. To this is added 70 ml. nitric acid (70%) until the
solution is acid to litmus
paper. A white precipitate is formed and is filtered out of the solution. This precipitate is hexamine dinitrate. It is thoroughly dried and is ready
for the next step of the
process. 95 grams of this white dinitrate is placed in a beaker or wide mouth jar. In another container place 60 grams of ammonium nitrate and 47
grams of 90%+ nitric acid.
To the 95 grams of white dinitrate add 228 grams of acetic anhydride. Add the ammonium nitrate/nitric acid mixture to the acetic acid/hexamine
dinitrate solution. A vigorous
reaction will take place. After the reaction subsides the liquid is filtered. The product thus obtained is washed twice with cold water twice with
boiling water. It is
dried and dissolved in the least amount of boiling acetone possible. This acetone is chilled and the product will fall out. Reduce the volume of the
acetone to 1/2 by boiling
and chill and filter again. Allow the acetone to evaporate and the type "B" R.D.X. is ready to use.
Now I had all the reagents to do this but i think the mistake I made was not researching before i did this. I had already made the hdn. I started the
synthesis weighing out my materials and adding them together under a small but very capable exhaust fan. The amounts I used were half of the stated
ones in the synthesis. Since there was no instruction on how fast to add the nitric acid mix to the acetic anhydride mix, i added it all at one time.
a vigorous reaction took place, as it stated, but it was extremely vigorous. It developed copious amounts of NO2 that was taken away by my exhaust
fan. it started boiling over in my 600ml reaction vessel so i put it in a 1 liter flask. the reaction was extremely vigorous. i went to get big rubber
gloves instead of small latex ones and when i came back, whitish fumes had evolved from the mix and my exhaust fan was not enough to take such a vast
amount of gas out. also, there were some black ash like flakes around the reaction vessel. i asume this was a decomposition product of whatever
product was made during this reaction. did i overlook an aspect like rate of addition or temperature? there was no cooling bath as it was not stated
in the synthesis instructions. im very pissed at myself for not researching this synthesis with u guys. btw there was no info on this synthesis online
(i looked forever).
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froot
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Consider yourself lucky you were trying to synthesise a nitramine and not a nitro ester. You did not control the rate of reaction using a pipette/sep
funnel, thermometer and ice bath.
Rule of thumb - When you ever perform a reaction in anhydrous conditions do it SLOWLY with some sort of feedback on the progress of the reaction, ie.
thermometer!
We salute the improvement of the human genome by honoring those who remove themselves from it.
Of necessity, this honor is generally bestowed posthumously. - www.darwinawards.com
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Microtek
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What was the source of the procedure? As you suspect, all the additions should have been slow and controlled (especially addition of nitric acid), but
when you say that there was no mention of reaction specifics such as temp or rate of addition, I get the feeling that the source is less than
reputable.
Also, what colour was your nitric acid? While it is possible to make nitramines with red nitric (ie., with a lot of dissolved NOx), I wouldn't
recommend it.
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The WiZard is In
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Quote: Originally posted by krazypunk50 | A few days ago I had a go at the KA method of producing rdx. the synthesis went as follows:
Dissolve 50 grams of hexamine (see Kitchen Improvised Plastic Explosives) in 150 ml. of water. |
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This is a bit confusing. A infer you used the method in Tim Lewis's
Kitchen Improvised Plastic Explosives, Information Publishing
Company 1983, for synthesizing hexamine. Yes?
His instructions for making RDX are detailed, that is not to
say they are correct, I did/are not planning to check them
for accuracy/completeness.
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krazypunk50
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Yes I did use that synthesis and you can find it on this website:
http://www.whitehonor.com/Kitchen_Complete.pdf
its under kitchen improvised plastic explosives II and under rdx mfg.
My nitric acid was not excessively reddish but it had a hint of yellow to it. It was distilled from potassium nitrate and sulfuric acid and the temp
went (tops) to 100 degrees celcius in an all glass 24/40 setup. It is about 96% but the synthesis called for >90% so I was in the clear.
I wouldve thought since this source was extremely extensive and it went into wonderful detail on how to make C4, it might be reputible. but i mightve
been wrong. So through my bunch of mistakes what i seem to get is that in this synthesis there must be controlled addition, cooling, and it must be
kept at a specific temperature. what is that temp? and please tell me if i am missing anything? (i feel like im sounding like a kewl but ive tried my
hardest not to)
ALSO i took a sample of some of the precipitate that didnt burn up and spilled over the flask. it was white just like rdx so i washed it in water and
neutralized it in sodium bicarb wash and water again just for the purpose of a burn test. when filtered it looked white with a hint of brown. the
deflagration was somewhat like rdx, except less vigorous. maybe very very contaminated rdx?
[Edited on 11-9-2010 by krazypunk50]
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Microtek
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The "Kitchen Improvised" series is generally a decent source, but there are some issues. I suggest you find a copy of either "The Chemistry of Powders
and Explosives" (which is usually referred to as COPAE) or Urbanski's "The Chemistry and Technology of Explosives" (4 volumes). COPAE is more directly
applicable to lab work, while Urbanski deals more with plant scale, continous methods. Urbanski,on the other hand, is much more thorough and with a
little thought it isn't hard to adapt those methods to small scale experiments.
Anyway, a temp of 70-75 C should be about right, based on a quick review of Urbanski.
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