Liquid-Liquid extraction: Hexane v.s. Dichloromethane

[Elite Engineer]

Is dichloromethane the end all be all best organic solvent for LLE? I

 

I only have hexane available, but I'm not sure if I'm wasting my time. Is DCM much better than hexane?

 

(additional info: I'm extracting eugenol from water, after I steam distilled cloves)

 

~EE

[John Cuthber]

If you are extracting eugenol from water both solvents will work.

One point to remember, eugenol is slightly denser than water and hexane is less dense. If you are unlucky, you will end up with a mixture that's the same density as water and it won't settle out.

You can avoid that, and improve the extraction efficiency, by saturating the liquid with salt.

 

Also, hexane has a huger boiling point, so it's more difficult to remove.

 

You can improve the purity somewhat if you make use of the fact that eugenol will dissolve in dilute alkali.

[Elite Engineer]

will the salt prevent the eugenol from sinking to the bottom?

[John Cuthber]

If there's more than about 10% w/v salt in the water, yes.

It will also lower the solubility of the eugenol in water