PRODUCING CELLULOSE NITRATE (From andrew at CMU)


I used to make nitrocellulose, though. It was not guncotton grade, because I

didn't have oleum (H2SO4 with dissolved SO3); nevertheless it worked. At first

I got my H2SO4 from a little shop in downtown Philadelphia, which sold

soda-acid fire extinguisher refills. Not only was the acid concentrated, cheap

and plentiful, it came with enough carbonate to clean up. I'd add KNO3 and a

little water (OK, I'd add the acid to the water - but there was so little

water, what was added to what made little difference. It spattered

concentrated H2SO4 either way). Later on, when I could purchase the acids, I

believe I used 3 parts H2SO4 to 1 part HNO3. For cotton, I'd use cotton wool

or cotton cloth.

 

Runaway nitration was commonplace, but it is usually not so disasterous with

nitrocellulose as it is with nitroglycerine. For some reason, I tried washing

the cotton cloth in a solution of lye, and rinsing it well in distilled water.

I let the cloth dry and then nitrated it. (Did I read this somewhere?) When

that product was nitrated, I never got a runaway reaction. BTW, water quenched

the runaway reaction of cellulose.

 

The product was washed thoroughly and allowed to dry. It dissolved (or turned

into mush) in acetone. It dissolved in alcohol/ether.

 

WARNINGS

 

All usual warnings regarding strong acids apply. H2SO4 likes to spatter. When

it falls on the skin, it destroys tissue - often painfully. It dissolves all

manner of clothing. Nitric also destroys skin, turning it bright yellow in the

process. Nitric is an oxidant - it can start fires. Both agents will happily

blind you if you get them in your eyes. Other warnings also apply. Not for the

novice.

 

Nitrocellulose decomposes very slowly on storage if it isn't stablized. The

decomposition is auto- catalyzing, and can result in spontaneous explosion if

the material is kept confined over time. The process is much faster if the

material is not washed well enough. Nitrocellulose powders contain stabilizers

such as diphenyl amine or ethyl centralite. DO NOT ALLOW THESE TO COME INTO

CONTACT WITH NITRIC ACID!!!! A small amount of either substance will capture

the small amounts of nitrogen oxides that result from decomposition. They

therefore inhibit the autocatalysis. NC eventually will decompose in any case.

 

Again, this is inherently dangerous and illegal in certain areas. I got away

with it. You may kill yourself and others if you try it.

 

Commercially produced Nitrocellulose is stabilized by:

------------------------------------------------------

 

 

1. Spinning it in a large centrifuge to remove the remaining acid, which is

recycled.

 

2. Immersion in a large quantity of fresh water.

 

3. Boiling it in acidulated water and washing it thoroughly with fresh water.

 

If the NC is to be used as smokeless powder it is boiled in a soda solution,

then rinsed in fresh water.

 

The purer the acid used (lower water content) the more complete the

nitration will be, and the more powerful the nitrocellulose produced.

 

There are actually three forms of cellulose nitrate, only one of which is

useful for pyrotechnic purposes. The mononitrate and dinitrate are not

explosive, and are produced by incomplete nitration. If nitration is allowed

to proceed to complete the explosive trinatrate is formed.

 

(Ill. 3.22.2)

 

 

CH OH CH ONO

| 2 | 2 2

| |

C-----O HNO C-----O

/H \ 3 /H \

-CH CH-O- --> -CH CH-O-

\H H/ H SO \H H/

C-----C 2 4 C-----C

| | | |

OH OH ONO ONO

2 2

 

CELLULOSE CELLULOSE TRINITRATE

 

 

Ahh, fer the NEW Cookbook....

 

-= Exodus =- '94