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Freezing base mix to easily pour off xylene safe?

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mansloth

Rising Star
I am a curious and inexperienced organic chemistry novice. I had an idea intended to make use of the last bit of magic in a jar and easily siphon off solvent but wondered if it would be safe. The idea was to do a final xylene pull from the base mix and freeze the entire jar to simply pour the xylene off later. I have not tried this yet and am a little concerned the this may be unsafe of behave differently that water when freezing. I do not want a messy and dangerous surprise. If this is safe and works at home freezer temperatures my thought was it would make solvent removal a breeze. If you only wanted alkaloids soluble in naphtha you could possibly pour off the xylene, add vinegar, freeze again and pour off xylene one more time, then basify and extract with naphtha in a smaller container. Is this safe or am I making any mistakes in the proposed method? Sorry if this belongs somewhere else, I am a frequent reader and new member.
 
What are you going to put in the freezer? If it is glass it will be messy indeed and you spill solvent everywhere because water expands when frozen and therefore cracks the glass because of expansion.Pyrex doesn't do that but AFAIK pyrex doesn't make long neck jars of the sort people find useful as extraction vessels.

What is wrong with simply siphoning off the xylene? I have these .5cm tubing I use and it works perfect everytime, no having to wait overnight for things to freeze... etc.
 
There is nothing wrong with the tried and true siphoning method the idea was to completely eliminate the chance of getting any of the base mix. The container could be anything. Mason jars sound like a disaster waiting to happen but if you found something that strong enough it could make it a lazier process.
 
I've done that method with success yet I don't do it anymore, and the freezing adds a lot in breaking an emulsion, if not for the poring off the non polar, it could be seen as an emulsion breaker on purpose. But yes, cracking the jar is a big risk. It would be advised to freeze the recipient of choice in advance several times with just water only to see if it suits.
 
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