steam distillation for essential oils

[Avery L. Breath]

Anybody have much experience with steam distillation?  Been looking into it lately and seems quite fascinating.  Specially for making essential oils.

I found a great home unit at a place online called heartmagic (it's a commercial site, so I won't post a link) and was wondering what people had to say about steam distilling in general.

Any input would be greatly appreciated.

[Stonehenge]

I use an expresso maker from time to time. It manages to do some sort of supercritical extraction as the steam is partly vapor and partly water. It's the easiest and least expensive way to do it. You can extract things that way which aren't soluable in water or just barely. Works well on poppy pods though I never was too fond of them.

[dergheist]

You can also use some 1/4" copper tubing coiled as your condenser and rig up a boiler from a small pressure cooker or other small metal container. I even Find that small stainless steel storage cans for dry goods work well as a boiler.   This works better than having to buy a fragile glass condenser and is much cheaper.  I like Stoney's idea, although I have never tried it I soon will be with some Sinuichi.     Just to see how it does compared to a crude extraction.

[Avery L. Breath]

Yeah good point Stoney.  I've used my little one pot espresso maker for kratom and a few other things too.  Works like a charm.  though I think I'm currently more interested in the whole essential oil thing for like aroma therapy type purposes and to play around with desert plants w/ alot of essential oils in them that my soxhlet isn't very selective in extracting.

Interesting though, I just ran across this page on erowid.
http://www.erowid.org/archive/rhodium/c ... yadontsay/
(I had no idea dill had such interesting oils in it.)

[Avery L. Breath]

dergheist, can you point me to a diagram of what your are describing?

[dergheist]

Just look to those ingenious people of the days when whiskey was illegal to make.  They will show you the easy and cheap way.  I know Edmund Scientifics, now called Scientifics, used to make a DIY perfume kit that had a pyrex flask with stopper,  the condenser was a coil of copper tubing and had a collection flask.  Simple, but it worked.  Since the galleries here are giving me trouble I cannot post a diagram or my setup. Sorry.

[visionarybear]

have also used espresso machine with success, mainly on herbal teas and the like, especially after the flatmate smashed my plunger and the ex has my other tea strainer and havent brought another yet...so out of necesity but def works well, only prob is it can extract more bittersd into the tea than simple soaking...

just a note, some metals shouldnt be used for heating consumables, cant tell u exactly which off the top of my head, but just a note to be weary of..

[dergheist]

Aluminum reacts to a lot of compounds and I would not recommend it.  Zinc coated items are a no-no for consumables, anything that you have used for non-consumables, etc.  Just use basic lab safety and the little thing on your shoulders and you should be okay.  Stainless Steel 400 grade alloys are usually excellent for consumables and are superior to most metal alloys for cost versus reactivity.   Copper could react to substances just depends on what you are extracting but for essential oils copper works great not to mention it detoxifies grain alcohols. (Or at least that is how the wives tale goes  :wink: )

[winder]

There is a good reason why pipes are copper in many places; copper is quite non-reactive.

Copper won't enter as a reactant, although it may catalyze other reactions.

[dergheist]

I beg to difer on that winder.  Copper when heated forms CuO, plus have you ever seen old copper plating on structures?  It tarnishs, that tarnish is a chemical reaction.  Copper is much more reactive than stainless steel, why it is used in pipes is that it can take a lot of abuse without breaking, does not oxidize (Rust) as fast as iron nor does it cost as much as stainless steel.  Copper reacts with a large amount of chemicals but is non-reactive to non-polar substances such as alcohols and most oils.  That is why copper has been used for distillation equipment in both processes, for its price and lack of reaction to chemicals in both processes.  Just my very brief and again vague little 2 cents of Chem as I know it.

[winder]

Of course stainless steel is less reactive, no argument there, but not all stainless steels even resist rusting.  SS304 rusts in tap water.

True that tarnish is a chemical reaction, although tarnishing of copper is rather slow.

Let's not debate over this.  Absolutes are not needed, practical choices are needed.

If copper is the only tubing material available, then it is adequate for use.
If stainless steel tubing is available, it is less reactive, but its heat transfer coefficient is lower, so the condensing efficiency is lower (need either thinner wall or cooler water to get same condensation as with copper tubing).

[Stonehenge]

Copper is not that toxic so I wouldnt be too worried about it. We need 2mg or so of copper in our diet every day. Glass makes a good condensation tube and should not react at all. Copper is much easier to work with and should do the job.

If all you are doing is distilling, you can buy condensers cheap. Years ago I made my own condenser out of glass tubing. I used an alcohol flame to soften it and bend. Distillation is not the same as what you get with an expesso maker. If you distill and aren't getting what you want or are extracting and get too much, try the expresso.

[Avery L. Breath]

Well, I've got a half dozen glass soxhlet type condensors around here and a distilling condensor I bought a while back as a lot for cheap (damn drunk ebay purchases!)  But I still don't quite see the concept on how to make the setup you guys are alluding to.

[dergheist]

Sorry winder that was a little petty on my part.  Anyhoo, Avery the condensor would be copper tubing coiled that would be attached to a boiler and the copper tubing would cool the vapor as the vapor traveled through the coils and then drip into the collection flask.  Very simple setup like I said.  You could even put a fan or such blowing on the coils to cool them.

[Avery L. Breath]

Ohhh, your talking about simply boiling the herbs then.  Is not what I'm looking to do.  But I see what your talking about now I think.