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emulsions from hell

Migrated topic.
Centrifugation at some good high speed breaks the meanest of the emulsions. But this is not useful to everyone.

Some people have suggested adding sodium chloride to increase the polarity of the solution and this allegedly helps breaking the emulsion. I am not able to understand the logic behind that and it has been found to be an useless tip by some guy I once randomly met.
 
^^SWIM also doesn't see the point in the NaCl addition. Yeah centrifuging is a good idea but with large volumes thats not so practical for most people like you said. Anyway normally with STB dreams SWIM doesn't have much emulsions but sometimes you get nasty horrible ones. Makes SWIM want to dream this FAFSA way. Speaking of which....actually SWIM will post in relavent topic.


Another tip 3:

Use a long glass rod and stir gently between the non polar and polar phases.

Tip 4: Credit to ron69 add not more then 1/3 parts alcohol to the water layer.
 
Vibrations. I have used a small vibrator to break up emulsions quickly. It works well, just don't use the wife's.

I've never used salt with a STB (and don't think it would work if I did), but will say that I have seen it work with A/B extractions if using minimal amounts of NaOH.
 
look.. about the salt thing.. IT WORKS..

SWIM knows for a fact it works, but has no idea about the chemistry involved for it.. Some people say it makes the polar layer more polar.. I just know that it worked for SWIM a couple of times for sure, no doubt about it

its a lot of salt you gotta use, btw, not just a pinch.. It is the most efficient way that worked for SWIM so far

SWIM's techniques for getting rid of emulsions are the following (in the order that he makes it)

Waiting
Vibration (tapping on the side of the glass)
Running hot water on the side of the container
adding more NaOH (very effective too! great if you're not one of those people that are against too high pH)
adding loads of salt

he only had to do the salt thing twice, the rest of the times it always solved with the earlier steps
 
That's it.

Basically salt makes the water MORE POLAR and less capable of dissolving some substances. If such substances are causing the emulsion and become insoluble in the water after adding the salt then the emulsion breaks down. However, adding salt can also cause emulsion in some cases. So it's not always a good thing.

Don’t add salt in the acid defat stage. SWIM found DMT HCl is very poorly soluble in water what is 10% salt. It actually precipitates out of solution a little bit! Much like the harmalas do when adding salt.

SWIM has actually extracted DMT (and other junk) from mimosa using JUST WATER, hydrochloric acid and salt. He did it by concentrating down the extract adjusted to pH 2 with hydrochloric acid, and then adding 10% salt. DMT HCl and a bunch of other junk immediately precipitated out of the solution.
 
SWIM wonders if a sonicator would work! Not everyone has these sitting around but they basically blast stuff with sound waves to shake up solutions or break cells. hmmm will try next time, also sonicating would help during acidic extraction by breaking up cells and plant material.

Anyway yea SWIM sees how salt increases the ionic strength of water and if it works it works. However in this case the non polar phase was well separated from the water phase so that was not the problem. The problem was the emulsion wanted to just sit in the non polar phase it wasn't going into the water unless it was rinsed over and over with clean sodium carbonate solution. So SWIM guesses it was some fatty substances making the emulsion that wanted to stay in non polar phase. In this case alcohol probably would have work the best to make the water layer more non polar to dissolve this fatty material.

The solution probably depends on whats actually in the emulsion which could vary with plant material, methods, solvents used etc.

SWIM thinks its good to compile these tips as everyone at some point has to deal with an emulsion from hell :evil: aaaaaarggg.
 
For emulsions that are mostly stuck in the water, add salt. Salt makes water more polar.

For emulsions that are mostly stuck in the non-polar solvent, add alcohol to the water. Alcohol makes the water layer less polar.

Another option, filter the non-polar layer through Whatman 1PS filter paper (not the water layer!). This paper doesn’t allow polar materials to pass through and should easily get rid of the emulsion.
 
Bubbles like this ?

Tapping helps, 100ml (added 20ml then 20ml and then 60ml) of a saturated salt solution (30g/100ml) didn't really. I don't know why but the first extraction (solvent) seems to clear up the fastest.

I haven't found the reason for those bubbles. Sometimes I put it all in, sometimes I let the solvent drip but the end result was the same. Now I just walk around and tap the separatory funnel and let it sit for a bit.
 

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