Sciencemadness Discussion Board

Make Nitrocellulose powder

Ankit1612 - 5-2-2023 at 11:06

I have nitrocellulose in fibrous form, and I want to convert it in powder form?
How should I start?

[Edited on 5-2-2023 by Ankit1612]

B(a)P - 5-2-2023 at 12:57

Laboratory of Liptakov has done a really good video on controlling the particle size of nitrocellulose using a mixed solvent system.
https://www.youtube.com/watch?v=oVZkPWxj5WE&t=49s

Herr Haber - 5-2-2023 at 16:30

Quote: Originally posted by B(a)P  
Laboratory of Liptakov has done a really good video on controlling the particle size of nitrocellulose using a mixed solvent system.
https://www.youtube.com/watch?v=oVZkPWxj5WE&t=49s


Very nice ! And the product seems even better than what I got from MCC.
A couple of years ago I was interested in indoor fireworks, seems the use of NC is common since it doesnt produce smoke. Never actually opened one for forensics sadly.

But back to OP's subject. I would not advise any mechanical methods. I was tempted to reduce fibre size, but not to the point to get powder by ball milling the cotton. I wouldnt do that, even wet with the NC itself.

LL method is *very* appealing.

Ankit1612 - 5-2-2023 at 18:58

I have seen the video Dr. Liptakov made three grain size And I also tried the same grain size which he made in the video. But at first 1g Nitrocellulose was not dissolving in 8.5g acetone, as shown in video. I mean it was dissolved but it was a very thick mixture.
And after that I added about 21ml of Ethanol. After that I did the same as he did in the video.

Herr Haber - 6-2-2023 at 09:19

See Urbanski tome 2 and 4 for a whole lot of information on NC solubility depending on the N percentage or different solvent / mixes.
Maybe your NC had a different N %

Ankit1612 - 6-2-2023 at 11:28

I used Potassium Nitrate and sulphuric acid to make this Nitrocellulose,
Do you know what percentage of nitrogen may present in that Nitrocellulose?

And to make its powder, What should I do?

Laboratory of Liptakov - 6-2-2023 at 11:55

In video was used nitrocellulose (NC) with content of nitrogen 12.2 % N. From store, thus professional material. Homemade NC can have
different grade of nitration. Therefore behavior in solvent mixture ( ethanol, acetone, water) can be different. Usually is necessary try own ratios between solvents. For example + - 10% from described method. I remember, that over 13% N (pure trinitrate is 14%) is behavior different and require more acetone against ethanol. Important is slow adding of water. And watching behavior after every adding of water. Pause 2 minute I reccomend. Between adding. At dropping is possible use water with 1% - 3% NaHCO3. For neutralisation NC on molecular level. Which is impossible at fiber- cotton consistency.

Interesting fact: the highest solubility of medium nitrocellulose is in acetone with the addition of 11% distilled water. (Urbańsky book)

Next advantage of this method can be separation high grade NC / from low grade NC.
Low grade NC stay in solution, because low NC is easy soluble in ethanol, but difficult soluble in acetone. But this step require vacuum filtration before pour in 250g of water. Method in video is basically only illustration. No exact and detail guide for all types od NC.


[Edited on 6-2-2023 by Laboratory of Liptakov]

Herr Haber - 6-2-2023 at 13:59

I dont think anyone can predict the % of nitrogen in home made NC :)
The best way in my opinion is to test your NC with acetone / ethanol / ether / mixes and compare to the literature. You should be able to guess if you have highly nitrated or low nitrated your cellulose.

As LL said, if some will stay in solution in acetone then you can already guesstimate. The try another solvent mix (acetone + ether for example).
Also consider that NC made from cotton balls is hard to fully nitrate because of how it's made. Think bamboo poles and the "plugs" they build every few meters.
Linters are prefered to make gun cotton I assume for this reason.

Ankit1612 - 6-2-2023 at 21:10

I think I should change my cotton!

Can I make flash paper, or you can say nitrocellulose from Tissue paper?
It will dissolve in acetone or not?

B(a)P - 7-2-2023 at 01:30

The cotton is not the issue. You can make very high nitrogen content nitrocellulose from 'cotton balls'.
Your nitrate mix and conditions are your key to success. As Herr Haber mentioned there is a wealth of information in Urbanski on nitrocellulose that will definitely help you improve your level of nitration.
You will need to consider the following questions if you want to try to understand the level of nitration that you have.
What reaction conditions did you nitrate your cellulose under and for how long?
How many moles of potassium nitrate and sulfuric acid did you use?
How much water was present?
How much cotton did you try to nitrate with your nitration mix?

Ankit1612 - 7-2-2023 at 03:39

I used 5g of Medical cotton, 50g of Potassium Nitrate and 80ml of 98% Sulphuric acid.

I performed this reaction in an ice bath.

And I left the cotton soaked in the nitration mix for about 12 hours in a Fridger.

Herr Haber - 7-2-2023 at 12:00

tissue or toilet paper is even harder to nitrate than cotton balls.
You can test it easily. Nitrate some cotton string, toilet paper, whatever. When you burn it you'll have a lot more residue than with cotton balls.
Be extra gentle if you want to keep your toilet paper / tissue intact. It will get brittle after the mixed acids ;)

Edit: last time I looked up numbers I remember wanting to finish the nitration with max 20% H20 and 10% being the minimum.

[Edited on 7-2-2023 by Herr Haber]

B(a)P - 7-2-2023 at 12:31

Quote: Originally posted by Ankit1612  
I used 5g of Medical cotton, 50g of Potassium Nitrate and 80ml of 98% Sulphuric acid.

I performed this reaction in an ice bath.

And I left the cotton soaked in the nitration mix for about 12 hours in a Fridger.


You would have had a pretty thick mix at that temperature and those ratios! I would have used a little more sulfuric acid, more like 100 ml. Also, once you have added the cotton to your acid mix and it has reacted for a bit, you can let it come up to room temperature for the remainder of the nitration. You should have reasonably high nitrogen content. As others have said, check Urbanski and do some solubility test to determine your nitrogen content.