In my endless hunger for new experiences in the field of energetic materials,
I tried to make some trinitrophenol, also known as picric acid.
So I went out of my cosey little house, and got me 20 aspirines,
(each containing 0.5 grams of acetylsalicylic acid) from the good people at bayer.
Once I got home I purified these using warm acetone.
Since many people asked me:"How do you purify aspirines with warm acetone?" Here's how:
Heat up acetone to around 50°C, while it's heating, crush the aspirine tablets
and add them to the acetone. Stir well so all that remain is a very fine dust
on the bottom of your beaker. Then filter with a coffee filter, and save the liquid.
Rinse the filter with a little more warm acetone. Now let all the acetone evaporate.
What is left should be nice white pure acetylsalicylic acid crystals.
Now what would you need for making this into TNP ?
- 140 ml of >95% H2SO4 (sulfuric acid)
- 20 grams of KNO3 (potassium nitrate)
- 10 grams of acetylsalicylic acid (ASA)
First dissolve the ASA in hot sulfuric acid, then add the KNO3. You might want to go
easy on the addition of KNO3, because this tends to heat the mixture quite a bit.
I don't think there is risk for an explosion when the TNP is in solution, but I don't recommend you try to find out!!
And definately don't complain with me when it blows up in your face, leaving you bleeding and full of acid (ouch).
Anyway, once the KNO3 is all added to the acid, you let is cool down nice and easy,
not applying extra cooling or anything, and give it an occasional stir,
so gasses can escape the liquid. (wich should be nice red by now)
Now dump this red liquid (when at lower temperature) in 0.5 liter of ice water.
You'll immedialty notice the change if you're not colorblind, it turns nice yellow !!
Leave it a bit, with good stirring, so all the yellow TNP comes out,
but while keeping the mixture as cold as possible.
Then filter this mixture (normal filter paper should be okay when you used enough of ice-water).
Don't forget to rinse with as cold as possible water (barely liquid)
Not too much, but make sure most of the H2SO4 is rinsed off.
Now you can sqeeze this out, and put it in the sun for drying,
which is going to be very difficult if there is still some sulfuric acid present.
From 10 grams of ASA, I got 10 grams of TNP, and I did it in 2 steps,
so you should be able to get some more out of it
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