Extraction Apparatus w/ Laboratory Glassware

[squiggly]

For this build I am going to create both a (1) refluxing apparatus and a (2) distillation apparatus for extraction (1) and solvent recovery (2). I plan to use hexanes for the initial extraction and during purification processes (filtration, defatting, water washing, etc.). Following that I will distill off the hexanes (collecting the solvent for later re-use) and introduce ethanol as a new solvent. If any terpenes distill off I will attempt to collect fractions at appropriate temperatures to purify them later--I will do IR analysis to determine what is/isn't coming out in the distillate--this will not be definitive but can provide some hints.

With the ethanol introduced, I will then distill much of it off leaving only a small amount which can then be dried over low heat, or vacuum purged. Again I will collect the solvent for re-use. Ethanol will pick up water as it distills and forms an azeotrope with water yielding 96% ethanol on distillation no matter how many times you distill it. A drying tube and vigorous drying procedures (both of the product and the apparatus) can be employed to keep this from happening, however in time all of the ethanol will be converted to ~95.6% at which time drying agents or high vacuum distillation may be employed to remove the azeotrope.

I have included some crude pictures of the apparatus, please forgive my artistry (or lack thereof).

http://i40.invalid.com/einl8i.jpg

http://i39.invalid.com/zmiae1.jpg

 

[squiggly]

I forgot to mention, I drew in the 105deg bent distillation adapter because it can be used in an alternate distillation setup where the condenser is held vertically, this wouldn't usually be necessary but might be with a graham coil.

I've also ordered a 2um fritted disc buchner funnel w/ vacuum adapter which can be attached to the erlenmeyer to vacuum filter the extraction mixture

 

[jump]

high vacuum distillation may be employed to remove the azeotrope.

Azeotrope percentage depends on pressure, in vacuum it shifts to more EtOH and less water, vacuumizing 95,57% EtOH will leave some water.

 

[squiggly]

Azeotrope percentage depends on pressure, in vacuum it shifts to more EtOH and less water, vacuumizing 95,57% EtOH will leave some water.

Yes, exactly.

The trick is to distill the 95.6% stuff over under vacuum--this leaves dehydrated ethanol in the boiling flask when you're done. However, this requires a 70torr vacuum (~70mmHg). My simple aspirator will only pull about the standard 29. So I'd have to add a vacuum pump and I'd definitely want to set up various safety nets in that situation. Most of the lab glass can handle up to 30psi (15psi for flasks and beakers generally), however this changes with temperature. These values are more than enough for this purpose, I've found vacuum pumps to be quite pricey, though.

Fractional distillation over drying agent would be my preferred method. It is also possible to add some benzene (which forms a lower-boiling azeotrope with ethanol-water, around 7%-ish) and eventually distill over the pure ethanol.

 

[jump]

It is also possible to add some benzene

Most often recommended to avoid any involvement of benzene, a hazardous substance.

 

[squiggly]

Most often recommended to avoid any involvement of benzene, a hazardous substance.

Thanks for the concern!

For the record, though, I'm well acquainted with the chemistry behind all of this. I got all my info from instructors, not google! Thus, I realize benzene's carcinogenic properties, the dangers associated with performing the extraction, and how to best carry it out safely.

This is sort of my bag :)

 

[Graywolf]

Here are some pictures of some of the glassware discussed. I also threw in a soxhlet.

 

[crom]

damn Graywolf what else do you use that stuff for?

 

[darkmatter]

wow and more wow/what in the hell

 

[squiggly]

The only thing not described above in my post pictured there is a soxhletic extractor.

This extractor has two tubes (sidearms) leading to it from the boiling flask. The material to be extracted sits inside the extraction body where the fumes from boiling solvent travel in through the top. Above this is a condenser (typically an allihn condenser for high capacity) with an optional drip tip. On condensation the solvent drips down on to the material to be extracted. Slowly this fills the extraction body with (cold) solvent. Simultaneously the second tube which enters at the bottom of the extraction body is filling with liquid equal to the solvent level in the body. This tube loops up and then down into the boiling flask--creating a siphon. When the tube fills, the siphon drains the extraction body's contents into the boiling flask and the process begins anew.

This apparatus is used for determining fat content of various samples generally. It also happens to work perfectly for MJ extractions--however, for my taste a reflux setup is cheaper and more efficient (exposing the plant material to heat helps with extraction). The advantage being that a soxhletic extraction is a set-it-and-forget-it type of extraction.

Most of this stuff is fairly easy to use/obtain. Its the chemicals and what people do with them that I tend to say "what in the hell" to :)

 

[Graywolf]

damn Graywolf what else do you use that stuff for?

Before registering Skunk Pharm Research, LLC, we used that equipment set up in my garage for our initial research. Squiggly didn't mention it, but a soxhlet makes killer coffee!

We've made a number of cannabis esters using this equipment, concocted potions, and last Christmas made some popular cannabis soap and massage bars for stocking stuffers.

With the inclusion of a separatory funnel, I also use this equipment to clean up other extractions, and have extracted essential oils from hops, for a hops farmer looking for a way to preserve and market his surplus harvest.

The glassware is all basic and the foundation to any number of chemical procedures and experiments.

 

[crom]

Thanks graywolf! How much would a basic setup go for that can extract the concentrates in a bho type of consistency? Recommended reading? links?

 

[Graywolf]

Thanks graywolf! How much would a basic setup go for that can extract the concentrates in a bho type of consistency? Recommended reading? links?

I usually don't extract with the glassware, just process the oil in it afterwards, though it can be used for that purpose. A one ounce column made out of a stainless steel turkey baster is under $10 and we pay $10, plus $1 an inch to have 1 " borosilicate columns made. They will extract a pristine BHO.

I use a funnel, a coffee filter, and a fruit jar for winterizing, which are a couple of bucks, and voille, a BHO absolute!

For alchemy, a 1 liter boiling flask, Alhin condenser, plastic bucket, and water pump could be assembled for under a couple of hundred bucks new, and there are a number of ways to go for heat. The stirring hotplate featured cost around $500 and a heating mantle is $100 plus change, not to mention the need for a varible heat control, but you can also use a simple hot oil bath.

Safety becomes the issue, as in what happens if something goes wrong???!!!

While you won't even smell the acetic anhydride as long as the condensing system is working, what happens if the coolant pump fails or you drop a flask full of the corrosive and flammable liquid?

Answers to that sort of question are beyond this thread, and I recommend that anyone wishing to play with flammable and corrosive liquids in the lab, take a formal chemistry lab course from an accredited source, if they didn't already in highschool or college.

 

[HerbalDreamin]

Answers to that sort of question are beyond this thread, and I recommend that anyone wishing to play with flammable and corrosive liquids in the lab, take a formal chemistry lab course from an accredited source, if they didn't already in highschool or college.

^Ain't that the truth! I'm in one right now and this is still a lot of mumbo-jumbo for me. I truly am fascinated by all this stuff, someday I'll be able to do this but for now I'm sticking to my SSTB and hot water bath....LOL!

Is there really a noticeable difference in the quality of the final product by washing the waxes and such out?

 

[Graywolf]

^Ain't that the truth! I'm in one right now and this is still a lot of mumbo-jumbo for me. I truly am fascinated by all this stuff, someday I'll be able to do this but for now I'm sticking to my SSTB and hot water bath....LOL!

Is there really a noticeable difference in the quality of the final product by washing the waxes and such out?

It is smoother and has a blander flavor than raw oleoresin. It is slighly more potent, but not noticeably so.

 

[GanjaAL]

Though I did well in chem... I hated the 5 step mole problems with a passion... Loved the labs and my lab partners though... ;)

 

[crom]

Any chance anyone has this all set up and can do a diy thread on it? Even if I need to do a refresher course online, I learn better by seeing it. Thanks for all the convo Grey, co2xtractor, and herbaldreamin! I want to step out of that butane hot water bath stylee, and get some more advanced techniques under thy belt lol. Till then I don't complain with the BHO I pull off. Thanks again all for such an interesting topic!

Cheers,
Crom

 

[deep buddy]

hey squigs and Gwolf . im really interested in solvent recovery systems. i have a good enough extraction process that im really happy with i just want to recycle my iso. what do you guys think would be the easiest method?

thanks in advance Deep

 

[squiggly]

I do in fact have this apparatus set up--this thread came as I was in the design phase, all the glass is now here.

A few things have changed, such as the orientation of the condenser during solvent recovery--but most of it is as outlined in the original pics. I've also installed a gas trap/scrubber in case reflux goes awry and my solvent ring feels like exploding out the top--thus far it hasn't traveled further than 1/8th the distances up the condenser--I am indoors in my residence and so decided to go overkill.

If you have any questions on how to set the thing up, how it works, how to run it, how not to blow yourself up, etc--go ahead and just ask here, or shoot me a pm. As far as a DIY thread goes, it really wouldn't get much deeper than a parts list and order of assembly. I will warn you that this setup is fairly expensive for someone who plans to use it only for oil production--a system like Graywolf's does a better job of this and is likely more "to-the-point" in terms of cost effectiveness.

This setup just makes sense for me as a chemistry dude--there are many things I can get into with this setup which are outside the scope of this post and forum. Those added functions are a large part of what made me pull the trigger on this setup--but if you insist on using lab glass for extractions I'm more than happy to help, just get at me.

 

[squiggly]

hey squigs and Gwolf . im really interested in solvent recovery systems. i have a good enough extraction process that im really happy with i just want to recycle my iso. what do you guys think would be the easiest method?

thanks in advance Deep

Need a run down of your extraction process to best answer this question.

For me I'd simply distill the stuff over under vacuum. You may lose some terpenes/flavor doing this without a vacuum--and you may lose some anyway with one if you are not careful and do not know the identities of the terpenes in your strain, some will be more volatile than others.

Anyone doing ISO extractions industrially would benefit greatly from a rotovap imo--there just isn't a better machine for the job. Also because you're going to be using the reclaimed iso for further extractions purity should not be a huge concern. Any impurities you'll have will all be weed related. Now if you want pristine iso back, it complicates things a lot but if you're just trying to save on your solvent bill--I'd go distillation.