Dealing with emulsions in sep funnel

[NamRa]

Hi I want to share my way of dealing with emulsions in a sep funnel.
I am not sure if this this a correct way and would like some opinions.

When put my base solvent mix in the funnel I wait a bit and than drain out all the base till I get to the emulsion stuff.
I wait a bit more so more base can find a way through the bubbles and come down.

Now I just add some fresh basefied water to break the emulsion.

Does anyone aelse work like this.
Or do most people add the fresh base when everything is still in the sep ?

 

[damon]

Can you explain a little more about what you are doing? The sep funnel does work with bases, but it is better used for acid washes. For acid washes you put your filtered NP solvent into the sep funnel, then add acid water several times to wash the good stuff out of the solvent. Assuming your basic solution contains the goods, I'm not sure how you are supposed to be washing the NP solvent with more base liquid, that seems to be defeating the purpose. I've heard of people using sep funnels to collect NP solvent off an STB, but it seems to me that sucking it off the top is a lot less work.

If you are doing a sodium carbonate wash trying to clean the solvent, you might lose a little, but it supposedly works. I don't bother, personally.

In any case, what I do to break emulsions in a sep funnel is to wrap the funnel with a hot rag. Wet a rag and heat it in the microwave a minute or so to get it hot enough so it is hard to handle, but not so much it dries out and catches fire. It might need to be heated several times to warm up everything in the funnel, but it works. I've also heard of people submerging the whole thing in hot water, or on its side, but that would be messy.

 

[NamRa]

I am just doing straight forward a/b.

So when I have finished mixing mhrb base with solvent I put it in the funnel to seperate solvent from base mhrb water.
When most of this is drained I end upp with a lot of bubbles. This is where I add the fresh lye water to.


I also take this bubble solvent mixture out of the big funnel and take it in a smaller one. That one I put in hot water

 

[Dr_Sister]

to break an emulsion you can add some water saturated with NaCl (table salt) and swirl gently. If your aqueous layer is completely saturated emulsions have a more difficult time forming

OR you could also try adding a co-solvent like MeOH, the principle is the same as above, the MeOH will end up in your aqueous layer.

OR stick a piece of wire into the funnel and swirl it a bit if the emulsion isn't too bad

OR run the whole mess through a (buchner) funnel with a layer of sand (last resort for Sister)


Over the years Sister has found that it is possible to "overshake" a biphasic mixture in a funnel, which leads to emulsions. After a while you will get a sense of how much you can shake it without forming an emulsion, sometime more of a swirling/shaking motion can work well.

Hope this helps