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Amon
01-11-2018, 07:04 PM
I finally got the condenser so now i have a basic distillation kit set up and i attempted to distill the essential oils of rosemary via throwing some water on top of the plants and distilling away. The issue, as expected to a degree, is that the oils are "dissolved" in the water (spread out) and it appears to be rather difficult to separate them with no advanced equipment like an oil extractor. I tried putting the distillate in a test tube with a small diameter in hopes that would allow a solid portion of the oil to collect on top but it failed.

Is there a way to clear out the oils? Any other ways to do this besides using an oil extractor?

Kiorionis
01-11-2018, 07:21 PM
The actual oils should float on the water. Otherwise you have hydrosols or something similar.

Amon
01-11-2018, 07:46 PM
We performed a steam distillation at the university lab using cinammon and the distillate was a milky white substance...even then, with a proper steam distillation setup the oils and the water were mixed.

Florius Frammel
01-11-2018, 07:49 PM
You should find a way to keep the plants out of the water. A cheap way could be to use a vapor pressure pot on which you connect your condenser. If you don't want to use a metal pot you can try this setup. But be warned. You'll need lots of plant material to just get a few milliliters of oil. Further it can be important how much plant material you use depending on the size of your vessel.

http://www.ursulapro.at/page29/page10/files/stacks-image-2f403e9-1200x848.jpg

I can recommend heating the flask with the plants too. But not too much!

Pot version:

https://www.distilling-fermenting-seminars.com/wp-content/uploads/EasyRotatorStorage/user-content/erc_76_1423175362/content/assets/distillationSteam_239x239-0.jpg

Dragon's Tail
01-11-2018, 07:56 PM
We performed a steam distillation at the university lab using cinammon and the distillate was a milky white substance...even then, with a proper steam distillation setup the oils and the water were mixed.

It's a problem with ratios, in my opinion (verified by scattered research in the area and some lab experience). You aren't going to get much oil out anyway, depending on the starting mass, and water will make a hydrosol with it. When no more oil can be absorbed into the liquid matrix, the remaining oil will float on top, where it can be separated in a funnel or volumetric flask.

I don't know how much you are using, but my suggestion would be this. Take your hydrosol (milky fluid) and pour it back into the boiling flask, and distill again with the herb. If you start getting an oil layer, make sure that only the hydrosol underneath it is used, or you will be wasting your time. When the plant matter is fully drained of its oil (IE you don't notice any change in the amount of oil being collected), then replace the plant matter, and start again, this time with the hydrosol.

Doing this will ensure that you aren't simply manufacturing more hydrosol, and in the process you might learn "how much" water to use with how much herb for efficiency reasons. Of course, the smaller the liquid amount, the more annoying the process because it requires more cycles.

Even so, unless you are using WAY too much water, you should see at least a droplet floating on top. Rosemary is supposed to have a good amount of oil in it. Care to give the recipe? (mL of water vs grams of plant matter). Was the herb dried before you started? Are the herb and water starting in the same boiling flask, or are you running the steam through another flask or a biomass flask?

I think the general answer is, more plant material, but cohabating (so to speak) the hydrosol will maximize your efficiency if the oils you are after will tolerate the heat, which I assume they will. Rosemary should be good as long as you don't boil to dryness and then scorch it, at least as I understand it.

Edit:

There is one more thing you might try if you get REALLY desperate and you are waiting on more materia or glassware. I have had zero luck with the process, but you could try salting out the oil. Oil and water don't mix, as every third grader knows. Hydrosols are just an annoying fact of life when the particle size is really tiny, so, taking advantage of that, if you can "distract" the water, then it will stop paying attention to the oil droplets and go after something else.
As I understand it, the procedure is to load the water up with as much NaCl as it will handle, or maybe a more miscible salt. The idea is that the water reaches a saturation point with the salt, and anything else (oil droplets, tiny particles) drop out of the already tenuous situation and can then be extracted.

Last resort only, because if it fails, then you will have a salty hydrosol that is, well, useless for most of our stuff.

Amon
01-11-2018, 08:49 PM
Dragon's Tail:

Not sure about the recipe, didn't calculate proportions.
I placed the plants and the water in the same flask, connected the condenser and the 2 adapters and distilled away in a sand bath. I got a colorless liquid with traces of what appeared to be oil floating on top of it, but the layer was both thin and not fully formed on top.
I also tried salting it out but i failed as well.

Worst case scenario, i will have to extract the oils by using Mercury. Regarding this way, would it be preferable to simply decant the Mercury/Sulfur mixture after the plant has been macerated in the Mercury for some time or should i distill it away?

Dragon's Tail
01-11-2018, 10:03 PM
... but the layer was both thin and not fully formed on top.
That's the stuff that you want. If you aren't doing a LOT of plant matter then you won't get much. My black pepper was done this way, and I literally had two or three little droplets after they gathered themselves up (very thin and barely detectable unless held in the light just right). If you want enough to collect, you need pounds of plant material, and you keep reusing the water fraction. that skinny layer will eventually fill out. It isn't a simple process that can be done. I'm wondering how big your flask is. If you are using water I would fill it no more than a quarter of the way with water and have the herb fill it the rest of the way to the top.
The sand bath is essential for this method, and you probably want to put a thermometer in the sand. It's often much hotter than the inside of the flask. You have to go real slow. IME, the sand needs to stay below 140, ideally below 120. Over 140, and I start detecting a scorchy smell in the distillate. Aluminum foil is your friend ;)


I also tried salting it out but i failed as well.
I think this is only valuable with really thick/milky hydrosols... That gives me an idea, I might have something to test this procedure on at the moment, lol. I've never been able to use it to extract oil, but I figured I would mention it.



Worst case scenario, i will have to extract the oils by using Mercury. Regarding this way, would it be preferable to simply decant the Mercury/Sulfur mixture after the plant has been macerated in the Mercury for some time or should i distill it away?

If by Mercury you mean alcohol... probably not going to happen. The will actually merge with the alcohol and go over the head with it. You can't pour it off. HOWEVER, if you are making a concoction from tincture, I've heard that you can take your distilled Mercury by itself (I believe, it might need salt) and distill again, thrice more and never to dryness. You should find something special in your boiling flask ;) IMO better than essential oil, but I've never done this procedure personally. Another forum member has posted success with it. I don't have all the details on this process, so you will have to research it, unless he happens to drop by this thread and dump some hints on you.

Dragon's Tail
01-11-2018, 10:38 PM
This should give you an idea of how much plant material you need:

https://www.essentialoil.com/pages/percentage-yield

and I can only assume that this is by weight as a percentage of DRIED plant matter. It says ~2% for Rosemary, so a 2 oz bottle would probably be around 50 grams (somewhere in there, I couldn't find the density easily). So for that much you would need 2.5 Kilos, and that's assuming a perfect yield.

elixirmixer
01-12-2018, 12:03 AM
Essential oils can be tricky. Key is to have a decent condenser/really cold water so as to get NO steam produced at the end of your system. Also, DT is right, it takes ALOT of material. I was using a 25 ltr boiler half full of material and struggled to get 10mls. (With Rosemary)

Amon
01-12-2018, 03:15 PM
Well i guess its going to be tough then. I have a 500ml boiling flask so its gonna take quite a while to get a decent amount. There is also no steam rising on the end of the system (i place the receiver jar in a puddle of ice cold water just in case but its not necessary).

As for the Mercury i didn't mean to get an oil separation. I meant that i would use the Mercury to extract the oils and then use the Mercury/Sulfur liquor as it is.

Dragon's Tail
01-12-2018, 05:42 PM
As for the Mercury i didn't mean to get an oil separation. I meant that i would use the Mercury to extract the oils and then use the Mercury/Sulfur liquor as it is.

In my opinion worth of investigation, for sure. Others might disagree. Tinctures are awesome in their own right, so what I do is set aside the first 30-60 mL in amber bottles before I start the experimenting with the rest. I take a few drops of the tincture while working with the extracted material of the same species sometimes too, just to get me in the mindset. This is the method I used to make a jellyball type of extract from the salts and the refined liquor.