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Best method for decanting? (specifically solvents)

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Analogue

Analogue

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SWIM has alway had a hard time separating the solvents from basically any extraction (specifically naptha/other paint thinners)

When using turkey basters (tried stainless steel and acid/base safe plastic) the solvent always seems to pour out of the tip almost immediately, making it impossible to transfer

When using flavor injectors or plastic syringes for solvents (except alcohols), the solvent stuck to the sides seems to warp/attack the rubber plunger which CANNOT be good for the extraction and makes the device useless, so..

Does SWIY have any methods for decanting that work well? perhaps a specific (type/brand) of baster.. perhaps glass? or a completely different method?

Any advice is appreciated!

(SWIM is aware of the ziplock separator funnel, but doubts its effectiveness for large batches)
 
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for small extractions (<100ml of solvents) I use pasteur pipettes
Pasteur_Pipets.jpg

For bigger extractions I suggest using bigger pipettes... you'll just have to invest in some gear. IMO the right tools make all the difference.
 
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a big 100ml syringe works awesome! I try and be extremely careful when doing extractions. I filter my spice saturated solvent before it goes into an evap dish or into a freeze precip jar.

How I do this is as follows.

I have a 100ml syringe that has the plunger removed. I put 3-4 cotton balls inside the syringe. When I am syphoning off solvent, I pull the solvent off with my syringe and then discharge it through the cotton balls and it drains out the bottom of the syringe ito the evap or freeze precip container. When filtering like this I am not as concerned if I get a tiny bit of something extra up with my solvent.

This has been my tek for years and it works perfect every time.
 
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If extraction is a long term project, do yourself a favour and buy a sep funnel.

I've tried decanting, syringes, pipettes, etc. Nothing comes close to a sep funnel. It is less than $30 where I live.

Decanting is very good for separation of solids from liquids but useless for separation of liquids from liquids.
 
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Analogue, The easiest easiest way to decant/siphon the NP solvent is when you have a relatively tall/narrow vessel such that there's a relatively small cross section between your two immiscible liquids. That being said, A Separatory Funnel, or Erlenmeyer Flask will help..A graduated cylinder would help, but likely not efficient due to overall size needed


If your solvent rises to the top, in a Sep Funnel, you can drain the most of the lower fluid out the bottom through the valve, and due to the taper, you'll have a nice deep layer of solvent(due to the taper/reduced cross sectional area in the Sep Funnel) to pull your solvent from the top via pipette. easy!

With an Erlenmeyer, you must get the size and total fluid amount correct, This will become apparent after explaining. After mixing your NP solvent with the mixture in a larger container, you can transfer this to the Erlenmeyer flask. You need a size such that that total mixture come almost to the top or the E flask. Again, this is because the taper at the top of the E flask giving you smaller cross-sectional area yielding a taller/deeper area of fluid which is easily pulled off with a pipette.

I hope those descriptions help you. Good luck. Let us know what you end up doing.
 
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alzabo said:
You can always freeze the water layer and pour off the solvent. It takes some more time but is easy.
Click to expand...

Very clever, but very slow. With a sep funnel I can do 5 quick pulls in an hour. Of course, it applies to A/B teks where there is no plant material.

Doing 5 freeze/thaw cycles probably would take more than a day.
 
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SWIM is in need of guidance in this area himself. SWIM has a Erlenmeyer flask but it's huge... 1000ml huge. SWIM also has a bunch of plastic disposable syringes ranging from 5ml to 60ml which are the leftovers from his earlier ventures into mycology. Using these syringes had occurred to him, but from what I'm reading these won't work very well either...

alzabo said:
You can always freeze the water layer and pour off the solvent. It takes some more time but is easy.
Click to expand...
Would this work for a water and NaOH mixture? I am curious as to whether adding NaOH changes the freeze point of the "water" layer... Neither myself nor SWIM has much knowledge in the ways of the chemist.
 
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SWIM will invest in a sep. funnel along with pasteur pipettes, the only issue being swim cannot order lab equipment online for awhile and will have to be patient with what he is using now/may try freezing it

@ lostkeys, the stb should still work as long as your fridge can go several degrees shy of 0oC "30% sodium hydroxide solution will have a freezing point of -2oC (29oF)."
 
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I use a 70ml syringe. I remove the plunger and use tape on the tip of the syringe, then I stick a few holes in the tape with a needle. I then add a small amount of water to the syringe, then I add the solvent/water to the syringe. The water should drip through at a slow rate, when all the water has gone through, you just remove it. Should give you a good separation. Works well with limonene/water and vegetable oils/water.
 
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