Nitrocellulose storage & safety question

[deepakpyro]

Recently i purchased 3 pounds of nitrocellulose powder. When i received, it was wet(i think some alcohol based additive added to prevent any self ignition during transport). Any one knows that additive please let me know what it is !.

 

I have used approx 1 pound of NC for making lacquer and testing different formula for cold pyro. My major concern is that, i am planning to make cold pyro out of rest 2 pounds NC, store it and use during festival season. How safe to store NC in form of finished cold fountain ? Considering it has oxidiser and metal added to it.

Any safety precautions i have take? Or use it right away for liquor ?.

Does Nc is friction sensitivity when it dry? Or sensitive when confined and stored?.

All comments welcome.

 

P.S NC grade which i have purchased is Industrial grade from reputed supplier.

[SharkWhisperer]

Recently i purchased 3 pounds of nitrocellulose powder. When i received, it was wet(i think some alcohol based additive added to prevent any self ignition during transport). Any one knows that additive please let me know what it is !.

 

I have used approx 1 pound of NC for making lacquer and testing different formula for cold pyro. My major concern is that, i am planning to make cold pyro out of rest 2 pounds NC, store it and use during festival season. How safe to store NC in form of finished cold fountain ? Considering it has oxidiser and metal added to it.

Any safety precautions i have take? Or use it right away for liquor ?.

Does Nc is friction sensitivity when it dry? Or sensitive when confined and stored?.

All comments welcome.

 

P.S NC grade which i have purchased is Industrial grade from reputed supplier.

Was it treated with a stabilizer like diphenylamine? NC likes to spontaneously shed its nitrate groups, especially in the presence of residual acids; diphenylamine acts as a scavenger to prevent autocatalysis. Common additive to smokeless powders, for example (usually around 1%), which last pretty much forever. Guitar lacquers, too. The alcohol smell may have been isopropyl alcohol--I've received NC in dilute IPA before by mail. In the US it is generally shipped "wet" to reduce flammability. You just dry off as much as you need and keep the rest wet and cold. Yes it is more sensitive when dry, but overall is not very shock or friction sensitive (we're talking high-quality NC here). Very spark sensitive. Burn a little of your NC powder to get an idea of flammability--it burns very differently depending on surface area exposure. Which is why guncotton/flashcotton disappears almost instantaneously when lit, but a pile of smokeless powder (NC and NG primarily) burns much slower than black powder under ambient conditions. NC requires a lot of containment (think gun chamber pressures) to deflagrate with force, and requires serious initiation force from a primary explosive charge to get true detonation.

 

Personally, for pure NC I would rewet it and store it in the freezer--that's how I store my pure NC in cotton format. Wet is safer (less flammable) and cold slows any background degradation. I'm not sure the advantage of IPA over pure water but there might be some additional benefit besides faster drying for use.

 

But if you have a mixture of NC, metal, and oxidizer, you'd have to look really close at all possible interactions to make sure everything is compatible, with both solvent and each other within that solvent--likely it would be better in that case to proceed with manufacture and store the final comp/product. If the MSDS doesn't show a stabilizer is included and you plan to keep it around awhile (more than a few months), then I'd seriously consider adding one. As I mentioned, diphenylamine is very common stabilizer (mops up nitronium radicals so they don't reform nitric acid). I think urea is used similarly, but you'd need to research that some more to verify this idea. If your NC turns color from white/off-white (i.e., yellowish to red/brown) it is degrading. If it has a smell, it is degrading. Homemade NC is notoriously unstable and contaminated (residual acid, nitrosulfur compounds; potassium salts if starting with KNO3 instead of nitric acid). It can be purified and stabilized, but it takes more than a few casual washes/bicarb soaks that most people do, and absolutely requires stabilization if it's not going to be used up immediately. It's the impure stuff that will cause you problems with degradation and autocombustion concerns when nitric oxides are formed/released/accumulate...

[Arthur]

NC shipped dry is dangerous goods and subject to heavy regulation, shipped wet it's almost unregulated in transport because in water it doesn't burn.

[deepakpyro]

Yes, NC which i got was "wet" when arrived. After shade dry of NC it lost its weight by 30%. Its pretty wet.

 

I am not sure on the whether it is treated with "diphenylamine" or not. When i asked my supplier about MSDS he wondered like i have asked out of galaxy question or a document from him.

He is pretty confident that NC is treated with stabilizer because he's into this NC trading for years and so far no incident of self ignition.

I have to do my own due diligence on stability of it is stored dry along with cocktail of oxidiser and metal in it.

Trying to get the MSDS directly from manufacturer to ensure it is treated with some stabilizing agent to store it safe.

I am gonna shove my NC in my freezer immediately considering boiling temperature currently all around my country.

Edited May 26, 2022 by deepakpyro

[Arthur]

Keeping it wet with water reduces the risk of hazard in storage, Articles made need to be considered as fireworks and stored appropriately. Perhaps a MSDS is on the www. you'd have to search.

[SharkWhisperer]

Yes, NC which i got was "wet" when arrived. After shade dry of NC it lost its weight by 30%. Its pretty wet.

 

I am not sure on the whether it is treated with "diphenylamine" or not. When i asked my supplier about MSDS he wondered like i have asked out of galaxy question or a document from him.

He is pretty confident that NC is treated with stabilizer because he's into this NC trading for years and so far no incident of self ignition.

I have to do my own due diligence on stability of it is stored dry along with cocktail of oxidiser and metal in it.

Trying to get the MSDS directly from manufacturer to ensure it is treated with some stabilizing agent to store it safe.

I am gonna shove my NC in my freezer immediately considering boiling temperature currently all around my country.

I'd probably be more concerned with unstabilized NC shedding it's nitrates and becoming weaker/more inert than I would be about risk of spontaneous combustion (seems pretty low with decent purity commercial NC to start with). But "wet" reduces likelihood of accidental ignition and cold will slow any degradation. When storing NC-containing comps, one essential consideration might be the potential shedding of nitrogen oxides and local nitric acid generation/accumulation and reaction with other components. But smokeless powder and ammunition based on stabilized NC can clearly be stored for many decades at room temp without any loss of activity, little if any degradation, and no risk of "spontaneous combustion" that I've ever heard of. It's typically the homemade stuff of questionable purity that can be problematic with respect to storage of any duration and gross incompatibilities with other chems.