Nitrocellulose Synthesis
Ok just a very brief intro here. As always, there are many websites out there describing the synthesis of nitrocellulose and I am just showing my method. This is quite a stable explosive but keep it away from any ignition source once it is prepared since it will ignite very easily. The preparation involves an easy nitration with little chance of runaway when done with this procedure. The whole process is pretty simple and not too much trouble. So here is how it's done.
The materials required are fairly easy to come by (of course depending on where you live). They are concentrated sulfuric acid, a nitrate salt, and cellulose (e.g. cotton).
And yes nitric acid can be used, but I generally use a nitrate salt. Which nitrate salt? I use either KNO3 or NH4NO3. The only real difference I notice is that with KNO3 there always seem to be insoluble particles left in solution but for this synthesis it doesn't bother me much.
The first thing is to measure out 60 ml of sulfuric acid. There is a slight difference when using KNO3 or NH4NO3. For KNO3 I use 36 grams (should actually be amost 51 grams based on theory but I use this), and for NH4NO3 I use 40 grams. The KNO3 can be dumped in all at once and may need some heating to help it all dissolve. The NH4NO3 will dissolve much better. Once the temperature is back down (if it went up) the cellulose addition can begin. I use about 4-5 grams of cellulose for these amounts, or just as much will fit into the nitrating bath. The temperature will rise during this addition, but I've never had any problems with these amounts. A runaway nitration may occur at around 70 Celsius, but again I've never had any problems with these amounts. I let it sit and nitrate for about 45 minutes to an hour with stirring every once in a while.
Now that the actual work is all done, it's time to clean it up. I usually add some cold water to the mix, stir, and decant a few times to get rid of the remaining acids. After this, I was the product with a sodium bicarbonate solution to neutralize any remaining acids that may still be present in the product. If there is acid remaining, it will take longer to dry out. The next part is filtering it and squeezing out as much liquid as possible. Then all that's left to do is let it dry out. The nitrocellulose will not burn properly if it is still wet.
So that's it, simple procedure and a great product. As always, take care during the synthesis as you are using dangerous chemicals. If the cellulose was nitrated properly, it should burn up almost instantly and leave very little if any residue. Here's a video of two pieces being lit.
