[Jellydonut]

Hi everyone,

Sorry, I may have posted this in the wrong section (I couldn't decide between this and Other Sciences). I realize that this is rather fringe chemistry, but here goes:

I've been interested in making essential oils for some time, and after doing some research I figured that soxhlet extraction would easily fulfill my needs by both extracting volatile organics as well as other substances within plants themselves for other purposes. However, one thing I didn't consider was actually the process of making an OIL as opposed to a watery mixture.

The Problem: After performing an extraction with water, I've created an amber, translucent solution. However, since I'm looking for OILS, I need to figure out a way to get them out of mixture. I realize that due to polarity issues there might not be much oil in my sample, but I figured there might be "stowaway" oils.

What I've Tried: I extracted some juniper using only water yesterday (and it smells great). I tried letting it sit around to let any layers form, but that hasn't worked at all, and I'm reluctant to add any other chemicals before I know what I'm doing.

My Proposed Solution: I was thinking of mixing in diethyl ether and using a separatory funnel type of setup, then evaporating off the ether. For the future, I'd try to use ethanol to dissolve more oils. Also, would it be possible to use ether from a typical home improvement store? Or would that be too dangerous?

For the future, I figured that my process would be more along the lines of:
1. Run the extraction with dilute ethanol instead.
2. Use ether afterwards to separate non-oils.
3. Separate.

However, I am getting a little bit of a spidey-sense saying I'm doing something wrong. If there's some process or something I'm missing, please let me know!

Thanks,
Jelly

[Arkcon]

Its a little hard for me to follow your missive, I'm having some disconnect with your title: Trouble with Soxhlet Extraction of Essential Oils and your casual mention of diethyl ether. 

Briefly, please don't perform a Soxhlet extraction using diethyl ether with an open flame as a heat source.  I just wanted to get that out of the way.

You're looking for the essential oils found in juniper berries.  This is a common flavoring ingredient in gin, so ethanol should be an adequate extraction solvent.  Unless you're looking for something else from this substrate.  But you can Google a bit for the components you're looking for and how the extraction is done commercially.

If you're trying to solvent extract the actives out of a water suspension of steam distilled plant materiel, that's another, separate process.

[Furanone]

I believe Soxhlet is not the ideal set up for extracting volatile essential oils for a number of reasons. Soxhlet is ideal for extraction of non-volatile triglycerides from foods, but for extraction of essential oils a steam distillation unit would be best to increase your yields, aid in separation of oil from the water infusion, and be most gentle on the original plant material thus not damaging the oil (ie through chemical reactions). Not to mention,much easier than what you are suggesting (and safer since not using diethyl ether).

Essential oil steam distillers are not too expensive. I have the one seen in this link below for about $457 US. See the separatory funnel after the condenser -- this allows for easy collection of the oil. Also, the sample chamber above the heating flask (for water only) keeps the juniper berries more protected so only evaporated water vapor hits the berries and carries the essential oils off with them up through system to be condensed and then collected. A thermometer goes at top of the sample container flask for temperature control. The oil separates on its own when it gets to a high enough concentration, but can also be enhanced by adding a concentrated salt (NaCl) to the collected water infusion to help "salt out" remaining essential oil from water.

http://www.aliexpress.com/item/Essential-Oil-Steam-Distillation-Kit-Lab-Apparatus-W-Hot-Stove-Graham-Condenser/32343992440.html?currencyType=CAD&src=google&albch=shopping&acnt=494-037-6276&isdl=y&aff_short_key=UneMJZVf&albcp=230049721&albag=13539119881&slnk=&trgt=63000991512&plac=&crea=en32343992440&netw=&device=c&mtctp=&gclid=CjwKEAjw67SvBRC1m5zPv4GboAUSJAB6MJlk0T0IqYGYd60veqoo1EVe1K7xz4UPrj2a3x8ZYhaMsxoCuxHw_wcB

[Jellydonut]

Briefly, please don't perform a Soxhlet extraction using diethyl ether with an open flame as a heat source.  I just wanted to get that out of the way.

Oh, sorry about my miscommunication! I meant to use the ether after performing the extraction (and once the boiling flask has cooled) to grab any nonpolar molecules. Is this flawed logic? I realize adding this process is probably slower than simply using a oil distillation kit.

I believe Soxhlet is not the ideal set up for extracting volatile essential oils for a number of reasons.

I really appreciate your concern. I hadn't actually realized there were such elaborate kits out there. I had only seen "kits" that consisted of  2 flasks strapped together with a Liebig. 
I figured I'd get my hands on a Soxhlet since I plan on using it for extracting other things like capsaicinoids and caffeine, among other things. I managed to get all the parts including the sand bath and flask for less than $130 since I don't have much money in my chemistry budget.

You're looking for the essential oils found in juniper berries.  This is a common flavoring ingredient in gin, so ethanol should be an adequate extraction solvent.  Unless you're looking for something else from this substrate.

I was actually going for the oils in the needles of the bush (which have a distinct, pine-like scent). Ethanol would still work for this purpose, right? And could I still use ether after the extraction to separate out nonpolars? Or would salting out still work for this?

Thank you guys very much for your responses and patience,
Jelly