Liquid-Liquid Extraction

Separation techniques are important in chemistry, and they won't always be as easy as filtration. Sometimes we need to separate two compounds that are dissolved in the same solution. Often we can take advantage of a difference in solubility or reactivity to perform an extraction. This is where one component is pulled into another solvent that is immiscible with the first, and we can separate the two layers using a separatory funnel. There is a lot to learn to do this efficiently, so let's get a closer look at how to perform this technique!

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[Kualinar]

I remember doing liquid-liquid extraction. Our teacher explained how it worked, then, we had a lab to put that in practice. He told us to use the second liquid in three parts. I instead divided my liquid into six parts, and stated that clearly in my report and exactly why I did it. My yield was significantly higher than that of the others to nearly 90% compared to the 65 to 75% that they had.

[chetanupadhyay]

I did this extraction recently during my organic chemistry lab... I separate ternary mixture using this technique... Firstly, I dissolved my mixture in ether... Then, the ether insoluble part settles down and ether soluble part dissolved completely in it (two compounds)... After that, I added small amount of sodium bicarbonate in it and there was a precipitate formation... Then, I transferred that solution in separating funnel and there was a formation of two layer... Finally I separated the all three compounds that were present in that mixture...
Really, this was a really helpful technique...

[MM-tzwe]

I am here for Dr Jamal Muhoza!!! well done. Mamello

[FquareLyrical]

I love this channel, I never questioned your explanation

[kylemoore]

Kinda fun to be listening to this while writing up validation documentation for Capillary Electrophoresis and HPLC instruments.

[BradSchmor]

I worked as a development chemist and there are some real-world problems that come along with liquid-liquid extractions, some of which can become a serious problem on large scale (12 L - 10, 000+ L). Anything bigger than 5 L is too big to shake by hand so you must use an impeller (basically an overhead motor with a long blade to whip the stuff). Emulsions can form which sometimes take hours or even days to break; gentle agitation sometimes helps with that. Sometimes we add salt (NaCl) to the aqueous phase to either help break emulsions or reduce the solubility of organics, especially if the solvent has appreciable water solubility, like ether or ethyl acetate.

Btw ethyl acetate remains in wide use in academia, but I promise you- isopropyl acetate is much better behaved in every way. Start using it.

[Pokemonzeldabro]

This is just the video I needed right now, thanks!

[andrewjones]

Another interesting lesson, Dave! Thanks for identifying the compounds this time! I think it adds to the completeness of the video!

[AbdelmoneimAAyed]

Thanks a lot sir. You are really great. Please don't stop making content!

[bunsenn]

I actually ended up using this method in another unrelated lab because of complications related to a recrystallization. Our product had dissolved but had insoluble impurities that needed to be removed.

[halimali]

thank you .I wished explain all methods to purification organic compounds

[urielpolak]

For all your chemical needs??!! I am happy its a scientist saying this not some random dude on the street

[elliejohnson]

I always wondered how the two layers are perfectly separated, I thought you just poured out a tiny bit after the first layer was dumped, I didn't know the stop cock actually held that fine line between the layers.

[ambarwaleed]

Sir i have a question? If we simply add benzoin acid in water and extracted in organic layer? Does it work? Or we require methoxy naphthalene?

[Thaumius]

Does the way that you hold the separatory funnel while mixing impact the extraction efficiency?

[TasneemOmar-dxwq]

What is the website or tool you use for video

[agile]

holy cow, I didn't think a forge would be a liquid-liquid extraction, crazy

[ahamdomar]

Good dude
I'm a pharmacist so useful for me

[Way]

I would say a great separation technique alternative to energy intensive distillation processes, or at least a great initial step for separations to save on energy costs

[yepyep]

Decantação

usa misturas de líquidos-líquidos e usa as propriedades da solubilidade
geralmente adicionamos um novo solvente à mistura que só se mistura a um dos dois componentes para separar as camadas
usamos um funil de decantação
a camada inferior é o componente mais denso, enquanto a superior é o componente menos denso
misturamos com movimentos suaves (desenhando um 8 deitado no ar com o funil de decantação) tendo certeza que está bem tampado (coloque a mão na tampa e não aponte o funil para ninguém)