Used Erlenmeyer flasks

[b-boy]

I just picked up 2 4L Erlenmeyer flasks. I'm replacing my old glass jugs that I use for 1 gallon starters. I can't keep the stir-bars going on the jugs because the bottoms are convex. It drives me nuts. I lost 1/2 my yeast last weekend because my starter threw my stir-bar and then erupted all over my basement. I needed a chisel to hack off the dried mess it made.

I got the flasks on E-Bay for $20 each. They look really clean. No residue, chips, or scratches. Unfortunately the seller has no idea of the history of the flasks, so I have no idea what they were previously used for.

How should a treat these flasks to ensure I get any leftover goop out of them? I'd prefer not to add anything like dioxin or nuclear waste to my beer if possible.

 

[acidrain]

Smell it. If it's chemical smelling, you may have a problem.
No smell? Wash really well and run through the dishwasher.
Sanitise by baking in the oven at 250 for 30 minutes.
Cover the opening with a piece of sanitized aluminum foil and store until ready to use.
When ready to use, a quick dunk in Star San is all that is needed.

 

[Singletrack]

Smell it. If it's chemical smelling, you may have a problem.
No smell? Wash really well and run through the dishwasher.
Sanitise by baking in the oven at 250 for 30 minutes.
Cover the opening with a piece of sanitized aluminum foil and store until ready to use.
When ready to use, a quick dunk in Star San is all that is needed.

Why bake in the oven? As long as it is clean, a quick dunk in Star San will sanitize it without the wasted energy of baking (and then running the air conditioning to remove the added heat). While I'm saving energy, skip the dishwasher too. It isn't very effective at cleaning an Erlenmeyer due to the small opening. Agree about the Star San.

 

[podz]

You will want to ensure that there are no residues clinging to the inside of the flask. This is called QUALITATIVELY CLEAN.

To get qualitatively clean, you can first empty a bottle of acetone in the flask and swirl it around for a while. If you can get a brush in there, better.

After the acetone bath, you'll want to give it a bath in a sink full of hot, soapy water.

Done.

The oven isn't going to remove hard residues. This only works for sterilisation after your flask is already qualitatively clean.

 

[obie]

that could be scary since the seller is unaware of the history. the flasks could have been sitting in a lab somewhere with dichloromethane in them. an under paid chemistry lab intern could have poured the liquid away and sold them off on craiglist

 

[b-boy]

Acetone makes a lot of sense. Acetone will pretty much dissolve anything. I'll follow that with a PBW soak and then star san. My real concern is that there will be some residue baked into the flask. Hopefully not.

I'm taking a chance, but for the $ I thought it was worth it. I can always re-sell them and get it back if they are a problem.

 

[podz]

Acetone makes a lot of sense. Acetone will pretty much dissolve anything. I'll follow that with a PBW soak and then star san. My real concern is that there will be some residue baked into the flask. Hopefully not.

I'm taking a chance, but for the $ I thought it was worth it. I can always re-sell them and get it back if they are a problem.

It probably goes without saying, but do the acetone work outside.

Stuff doesn't cling to borosilicate as easy as it does to normal glass because the pores are a whole lot smaller.

 

[b-boy]

My flasks showed up today. They are very clean - no scratches or any sign of residue. I think I got a great deal. They are huge.

Now if I can only avoid breaking them. I had a 5L flask that lasted 2 weeks before I cracked it.

 

[BigPerm]

that could be scary since the seller is unaware of the history. the flasks could have been sitting in a lab somewhere with dichloromethane in them. an under paid chemistry lab intern could have poured the liquid away and sold them off on craiglist

Honestly, I wouldn't trust standard homebrew cleaners for this. If these came from an organic or inorganic chemistry laboratory (especially), you potentially have very dangerous trace chemicals in your flasks.

With having no idea where they came from, I personally wouldn't use these without an extremely harsh acid wash, base neutralization and acetone rinse. Maybe it's overkill, maybe its not. With no knowledge of history, they could have been used for anything, from pouring agar plates to making meth. You are obviously free to use your own judgement; i'm just posting this so you're careful.

 

[b-boy]

I have a bio-chemistry degree and I worked in a chemistry lab for 6 years, so I'm familiar with what could be in the flasks.

I'm going to thoroughly clean these, including an Acetone wash. These flasks look new - no scratches, no residue, so I'm more comfortable than I was when I ordered them.

 

[BigPerm]

I have a bio-chemistry degree and I worked in a chemistry lab for 6 years, so I'm familiar with what could be in the flasks.

So do I, and I still do; hence my warning. All I'm saying is that I definitely wouldn't use the retired flasks from my lab (or the inorganic lab I worked in as an undergraduate...god) for anything I was going to consume, regardless of condition. I, personally, would never use a flask that I didn't explicitly know its origin. IMO, its worth the expense to buy new.

Just my 2 cents. But you know the risks, so I hope it works out for you.

 

[b-boy]

Appreciate it.

 

[podz]

So do I, and I still do; hence my warning. All I'm saying is that I definitely wouldn't use the retired flasks from my lab (or the inorganic lab I worked in as an undergraduate...god) for anything I was going to consume, regardless of condition.

Every chemical is solvent with some agent or another. Organic chemicals are solvent with acetone, inorganic with ammonia. Both are readily available to the average person. Just don't go mixing your solvents and you're good. Contamination is not an insolvent condition; especially fungus is good at solving radioactive contamination.

 

[b-boy]

I did get a little more information on my flasks. They are from a Pfizer lab that shut down. Hmm...could be Viagara in them. I'd better be careful.

 

[riderkb]

How should a treat these flasks to ensure I get any leftover goop out of them? I'd prefer not to add anything like dioxin or nuclear waste to my beer if possible.

If you try all the lame-ass cleaning methods suggested by these chemo-phobic wieners and are ready for some nuclear waste, send me a PM. I'll hook you up.