Ethanol recovery via SPD

Just curious what the drawbacks are to this method of recovery as I’ve seen it discussed a little here and there. Currently operating small scale and would like an intermediary option for recovery for a while before going rotovap. My circulator is regrettably not a chiller (Fischer Isotemp 3028HD) but of course I am operating a cold trap and I do have access to a diaphragm pump. What would a procedure with this equipment look like? Should I be concerned about volatiles recovered along with the ethanol?

You can but it won’t be as dialed in and painfully slow. Just dump ice blocks in a cooler and circulate through the condenser


Buy a alcohol distiller for $125 and recover a gallon every 4 hours. That’s better than what your proposing.


Just a typical stainless steel still would really do the trick? I just need something to work for me for a little while before I can finance a rotovap. Looking at Chinese models, are there decent options for under $2k?

I was gonna get this, lol and upgrade it with a coil condenser

same boat as you, brother.

I did this same thing then immediately upgraded to a frenkenstein buchi I found online. I think I have 1k into my 3l buchi now with a Dewar dry ice condenser and an Aldrich super coil condenser. A 5L re-501 China roto should be about 1k shipped I think


Chinese are Ok but so are used
What volume do You Need to Evaporate ?

O and for a chiller i often. Use one of these iT s t

the internal of an Office water cooler a small Bucket and a aquarium pump Gives a steady 7C on a 4 liter boiling flask


That vigreux column will slow down your recovery and is completely unnecessary. Other than that though, that’s pretty much what I’m rocking until I can order a roto.

Edit: I recommend a sep or addition funnel with a ground glass joint and claisen adapter, along with another 1l (prefferably 2l) round bottom flask for the collection vessel. It makes adding tincture to the BF a breeze. That and the larger receiving flask will make it so you don’t have to break vacuum so often to add tincture or empty receiving flask.

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Probably about 5L is what I’m thinking. 5-10ml ethanol per gram of crude for my 1-2L setup.

lookup DIY window ac glycol chiller

Also what @coppertop says, a claisen is all thats needed for the distillation really.

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You. Need reflux to make 96% etho
So a real vigreu or a higher head
Your evaporated azeotrope ethanol Will be less then 96% in a short path
Depending on the amount of water in the solution

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i would say reproofing is a whole different ball game and should happen at a separate step from this one