No immediate qualms with DMF… just read the MSDS and be safe. Most glassware can be cleaned without resorting to destroying the glass surface, as HF would. I would use sandblasting if I needed to go that route, rather than assume the risks of using HF.
just dont work with fluorine basically ever lol
I cannot say I blame you… except for fluorinated polymers. Those are usually very nice to work with when dealing with super sticky stuff like cannabis resin.
hi im fairly new and still learning how long do you have to wait for glass to cool down in order to clean ibreally dont want any accidents
Depends on a lot of factors like glass type, thickness, variation and connections, temperature differentials, solvent type and temp going in, etc. Generally it is best to wait until you can touch the glass without burning yourself.
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the glass isnt too thick so i guess its better to wait
Thinner glass can actually take more thermal strain, that was explained to me by a scientific lamp worker. Glass has a low thermal expansion coefficent, and is a good insulator. If it is thin it will distribute heat quickly to the glass allowing all the glass to expand at the same rate. If it is thick the outer parts find they want to move, while the Inner parts are still warming up.
Try this experement, get a glass rod and heat it with a torch to red hot at the tip. Slide your finger down the rod to the hot side. You should be able to get fairly close to the heated part because of the insulating ability of glass.
See how the artist holds the rod that is molten on the end without gloves.
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@dab-boss @Soxhlet is correct. However, you should not be using very thin glass for vacuum processing, especially if there is a stir bar moving inside it. Make sure your glass is rated for vacuum. That said, original incandescent and fluorescent light bulbs are vacuumed and partially backfilled with argon or other inert gases. They heat up and cool down all the time… but they don’t have moving parts inside them bumping around or liquids rapidly taking heat from the surfaces either.
Just to second, third and fourth it: Never, ever, ever use HF. At PSU there is a special sealed lab for working with HF, because it’s really quite awful.
Realistically I stop at alkonox. Most glassware is cheap these days, even if it’s not a serious risk/reward calculation needs to be done before using these methods.
Just my 2c, hate to see someone seriously harmed trying to wash their coffee cup with Aqua Regia.
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thanks
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you’ve seen my coffee cup haven’t you 
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Any suggestions on good systems for cleaning large quantities (100+) of mason jars crusted in old oil/sauce? We are currently using large amounts of acetone, iso, liquinox in succession, but I’d love to find a way to minimize our use of acetone/iso.
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my $0.02
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anybody tried Monster energy drink as a cleaner?
that shit can do shit brake cleaner cant.
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Does anybody have any recommendations for a sponge or brush that does not fall apart or disintegrate?
We need a pro version of these. The bristles are too loose and long for this, but if we had a pro version of silicone glove scrubbers for large glass vessels and buckets, I’d be sooo happy.
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What would be the easiest way to clean a short path system that was exposed to Piperonyl Butoxide and Pyrethrin? I did my standard wash. First I put ethanol in my boiling flask and heat up Until it evaporates and takes all of the remaining distillate into my receiving flask, cleaning the head and condenser as well. The I take it all apart and soak in an alconox solution for about 30 min and scrub after. Then I rinse with tap water and then rinse in DI water. Should this be sufficient in cleaning the pesticide residue off of the glass? I really don’t want to run again until I know for certain that it is free of pesticides as I don’t need another failed COA. Thanks in advance for any input.
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If you have in-house analytics, it’s pretty easy to test and see if the glass is clean. Even without them in-house, you can easily send out some tests to see from a 3rd party lab. It’s worth the peace of mind to spend the money, imho.
Perform another distillation of ethanol. Test the distilled alcohol to see how successful you were. Then perform some water distillation (of distilled water. Don’t want to have to deal with residual mineral content). Test the distilled water, and then feel really good (or really bad) about the cleaning job.
I had a similar experience with different pesticides, and it took three rounds of cleaning and testing to get it right. I never figured out where my remaining contamination was after the first round, but I was far more thorough with each subsequent pass. Haha.
Keeping my fingers crossed for you.
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Thanks buddy. I will have to go that route unless someone has a sure fire way to get rid of this shite. In house analytics will be coming in the future.
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Has anyone come up with some sort of ethanol reflux cabinet for cleaning resin off loads of glassware? I’m imagining something like a vacuum oven mixed with a hot food moisture cabinet like this here:
Load the glassware onto dishwasher-like racks, add a couple quarts of ethanol to the warming pan, then lock the doors and let it cycle. It would warm up the ethanol to boiling or close, vacuum assisted like a large vacuum oven or rotovap, having a cold trap or condenser in line to return ethanol to heating tray. All the oils or resins in the ethanol solution should drip to the pan/collection tray at the bottom, which could then be discarded, or processed for distillate depending on practices followed.
Materials and safety-wise it probably would be rated similar to a vacuum oven or rotovap, assuming it’s made using stainless and glass construction with appropriate gaskets.