Purple nitric smoke?

[Martijn]

I have made a stupid mistake in waste treatment. Possibly creating an explosive compound.

I wanted to test some stockpot slimes that i cemented on silver plated copper bars for the first time. It had silver pieces in it that fell off during cementing, so i rinsed and decanted the slimes with boiling tap water and distilled water a couple times to get rid of HCl traces.
Put it on low heat with distilled water and added 5ml of nitric 50%. To dissolve the Ag and any Pd. It started to bubble a bit at first. Almost no brown fumes.
At 70 degrees it started to make purpe smoke!

So I took it from the heat to see if the smoke cleared and i have an idea how to proceed.
It turned clear as it cooled but left some dark purplish crystallization on the glass.

Thinking back i may have empied some iodine - potassium iodide from a test tube in the stock pot.
So its probably that.

But did i create nitrogen triiodide and how should i neutralize and safely discard the possibly explosive compounds?
I expect leaving it wet will keep it stable for now.

I have no problem discarding this bit of pm's that may be in there, recovering them would be nice.

But safety first, so any help is appreciated.

Martijn.

 

[Martijn]

Reading up a bit it is very unstable and sublimes at -20 C, so anything in there would have exploded or evaporated off already? I hope.

 

[orvi]

Reading up a bit it is very unstable and sublimes at -20 C, so anything in there would have exploded or evaporated off already? I hope.

I know that NI3 is made in basic enviroment from ammonia and iodine. I wonder if it could be prepared in acidic conditions... I think sulfite will kill all iodine and also drop the gold. But with NI3... I do not exactly know how it behave with reducing agents.

 

[Stibnut]

I can't be 100% certain that NI3 can't ever form under acidic conditions, but it seems very unlikely to me - any ammonia would be present entirely as ammonium, which doesn't react with free halogens. Also NI3 is so ludicrously sensitive that it would almost certainly have detonated just from heating, setting down the beaker, or the like if it were present, even wet. I'm pretty sure you just have elemental iodine, which you can reduce back to iodide using sulfite/SMB as orvi suggested and then rinse away with water.

 

[Martijn]

Thanks guys.

 

[Martijn]

Proceeded as usual, no problems. Yet..

 

[BlackLabel]

But looks cool, please repeat it for a video! ;-)

 

[Martijn]

I just read that the forming of purple smoke upon addition of a bit too much HCl is actually how iodine was disvovered during the production of nitrates from burnt seaweed.
https://en.m.wikipedia.org/wiki/IodineBut yeah, once it's no longer scary its looks pretty cool.
I dont know if i will have iodine in with pm's anytime soon.

 

[jobinyt]

I used to make and play with NI3. Always thought, and never experienced otherwise, that it is stabile when wet - dry however ... it might as well be spontaneous.