Hey guys need some help.....so when a extraction is finished using heptane it has cooled to room temp then into the fridge. Everytime I put it into the freezer within a minute or 2 I see droplets forming on the underside of the saran wrap. Knowing the stuff aint supposed to touch plastic I took that wrap off quick and chucked up before it started dripping back into the plate. it seems to evap and condense on the wrap! never noticed this before. So right now its in the fridge as I am afraid to keep loosing stuff everytime this happends. WHAT CAN I DO??? I am STUMPED! thought maybe put it into a mason jar and let it freeze out in that. But would the top coating on the mason jar be similar to plastic in the fact I don't want to let it hit that and drip back down? PLEASE any help would be appreciated this is a new problem and I am not home right now dealing with it where I am so I have a limited time to deal with it.

You're not losing anything-- it's just condensation. I've used mason lids for years-- they're fine.

It all depends what your saran wrap is made of.
Check compatibility of various materials plastic film can be made of by googling phrases like "plastic heptane compatibility", "polyethylene heptane compatibility".
https://www.plasticsintl.com/chemical-resistance-chart

You can find that hdpe is not bad when the temps are low (room or lower). Short exposition is not a problem here. Especially when the temps are low (fridge, freezer).

But there are even better materials (PVC, PET) which are fully resistant. It should not be problem to find such plastic film.

Always keep it sealed.

Ok THANK YOU! what I ment by loosing it was that the heptane seemed to evap off the dish but no where to go condensed back onto the underside of the plastic wrap. Now I know having the stuff touch plastic is no good so I didn't want that to drip back down into the dish contaminating everything so I riped the plastic wrap off and chucked it loosing what ever condensation of heptane was on there....did that twice, it deffinitly was heptane condensation cause I thought maybe it wasn't sealed right or something or water droplets from the air inside the plate but the wrap with the condensation on it smelled strongly of heptane.....I wasn't sure about jars never used them but THANK YOU!!!

Pete666 just saw your post thank you for answering as well! trying to figure this out before I have to go home! so you guys answering fast helps! Thank you I am going to use the jar for today but like the ease of the plate when gathering everything up so ill deffinitly check what wraps are ok! Thanks again

No prob. Never use any lid or cover with rubber or plastic if you don't know the materiál or its compatibility

Just thought of something I have rolls of PTFE sheet from my BHO experiments...that is resistant to butane I am sure so should be for heptane maybe next time laying that over the plate the only problem would be sealing it maybe folding it over the sides and using some kinda tape as a seal as long as the tape is toward the bottom of the sides of the plate or the bottom I don't think anything would come in contact with it. Anyone ever done anything like that?

Ptfe is perfect. Rubber band?

AHA! And that is why I am still a noob! LOL

Btw you use plate? Beaker or jar is better imo.

yeh using pyrex dish's....seems it would be much harder to get out of a jar or beaker