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I had a quick look in "Destroying hazardous chemicals in the laboratory" but there is no entry for AIBN (or any related compounds).
ReplyDeleteStep one: take some organic solvent, i.e. condensates from rotovap receiving flask, open the old 25g AIBN bottle (wear face shield), pour the shitty solvent in, stir occasionally with a spatula. Step two: pour the whole damn thing into a large waste barrel that already has some waste in it. Wash down the funnel with some additional waste solvent. AIBN is shock sensitive only when dry. It will gradually decompose in solution over few days, evolving few grams of N2...
ReplyDeleteI would not do this with a 25 kilo drum, but 25g does not scare me.
I haven't DONE it, and I wouldn't do it at a full 25 gram scale on the first try, but I'd guess that Fenton chemistry would work to decompose AIBN.
ReplyDeleteI was just tasked with getting rid of about 100 g of the stuff. After checking all the usual resources, I concluded the most prudent course of action was to just call clean harbors and let them deal with it. Sure, that quantity is *probably* OK to go into the organic waste drum as long as it's wetted. But why chance it?
ReplyDeleteIf no certified disposal company was available, I'd dissolve small batches (2 g) in toluene, add NBS and heat it up. Probably the most expensive way to produce bromotoluene...
ReplyDelete• Saturated aqueous solution of sodium dithionite, rigorously stirred, chilled to 0°C in a properly working fume hood with blast shield.
ReplyDelete• AIBN in methanol, slowly added (3 drops per minute) via funnel with stopcock or cannula.
• After addition of AIBN, allow reaction to proceed at 0 °C for at least 1 hour. Dithionite should reduce diazo to hydrazide.
• While still vigorously stirred at 0 °C, slowly add saturated solution of cupric sulfate to sequester cyano species.
• Allow the reaction mixture to warm to ambient temperature over at least 1 hour. Dispose in heavy metal aqueous waste.
Does this method have a workable/relevant citation? Might be useful for our correspondent.
Delete@CJ
ReplyDeleteSorry, this method was something improvised back in my grad school group. I haven't done it in a while.
It served as an alternative to using smelly thiols or massive amounts of stannous chloride (both of which reduce diazo).
AIBN is recrystallized from methanol anyway, plus methanol serves as a proton source to intercept the hydrazide.
The postgraduate side of me agrees with MA at 8:14 AM. If you can afford proper waste disposal, use it.
Otherwise, another cheap option is a slurry of zinc powder in ammonium chloride. Just Google Scholar Search zinc reduction of diazo.
In case any adventitious cyanide is generated, it will form a strong complex with zinc(II). Plus the ammonia will keep the system buffered.
Again, the resultant products should still go into heavy metal aqueous waste. Sorry that I can't provide more details.
Find a polymer chemist in need. It's a terrific thermal initiator.
ReplyDeleteHah, I remember late 2011 when I ordered AMBN to get started with some polymerizations in my company. I'm in Canada, and at the time I couldn't buy AIBN or AMBN from sigma. (I can't remember why.) We bought a "sample size" of something like 300 grams (if I remember right) from the manufacturer. Each dispersion polymerization only requires 0.25 g. And even better, in grad school my RAFT polymerizations needed maybe 5-50 mg.
DeleteFind a local, domestic CRO willing to take some of your excess reagents off your hands, and give them the bottle as an extra freebie.
ReplyDeleteAIBN is also known as Vazo 67. The 67 comes from the fact that it's 10 hour half life occurs at 67 C. So, you could put in for example toluene and reflux it for a few hours to kill it.
ReplyDeleteHonored that you're commenting here, Auntie.
DeleteAzo's are flammable, reactive solids, and can undergo self-acclerated decomposition at elevated temperatures. For AIBN, the danger point is about 50C. Heating these guys up in the presence of a flammable solvent--especially one with a boiling point greater than 50C, is a recipe for disaster. Not to mention that one of the degradation products of AIBN is a toxic compound known as tetramethylsuccinonitrile, TMSN. You don't want to mess with TMSN.
ReplyDeleteFind a local incinerator and let them do the job the correct way: burn the AIBN. If you can't do that, run a waste polymerization with the AIBN and then dispose of the polymer according to local regulations.
Our waste company doesn't want it because of the dangerous qualities of this chemical. Could you explain more about this waste polymerization?
DeleteI interpret "waste polymerization" to mean consume the AIBN by running a reaction with some cheap/available monomer then throw the product away(styrene to polysytrene?) Yes doable but if you have much AIBN may require large or multiple runs where appropriate precautions need to be applied. I have done this with a few things but if can avoid such "remediation" its better as can be illegal to "self treat waste" Regardless I would first review AIBN in Prudent Practices if cited there or other such Safe handling reference as could suggest how might to deal with.
DeleteAdditionally I would be greatly concerned about a "waste company" refusal to handle as in the great scheme of things there are many chemicals far worse that are likley to come across in most chem labs>
Agreed on the "far worse" aspect, but the problem is meshing EPA, DOT, OSHA, and disposal regulations into a coherent argument, as none of them agree. Due to many manufacturers putting their product as "temperature controlled" in section 14 of the SDS, this immediately limits which waste companies you can use down to a very small handful. This would require a truck and facility permitted for temperature controlled waste. So, the question is now "how do we remove the temperature controlled aspect," which would require a high-hazard field chemist trained for situations like these, which is again dwindled down to an even smaller handful. By the time you get to this point, upper management will likely shoot the job bid down entirely because it's teetering on the definition of "treating waste," (which is also not allowed by EPA), the fines for doing so can be exuberant, and now outweighs the slim profits involved. TLDR; I'd recommend finding a replicable way to dispose of any high-energic virgin waste to avoid any problems.
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