Fractional distillation

gwpharms

Well-Known Member
It is tricky. Never done it myself with cannabis but I have short path distilled a few other compounds way back. Aka molecular distillation
cannabis has shown new light on the glassware needed making it rediculously expensive. There's a lot of people selling kits now. Most of its Chinese glass like chem glass or laboy.they all make claims how their short path condenser is specifically designed for THC and better than the other guys becaus????...e of blah blah blah but it's just the same design that glass manufacturer has always made. There is a efficiency benefit to the jacketed condenser , which is why it now cost 5 times more than the un jacketed. If you have lots and lots of money and want a turn key easy to operate non stop THC machine, you want a Pope aparatus
 

dabbindylan

Well-Known Member
I guess my real question is where can i get the glassware to do my fractions.. Links would be helpful. Im processing lots. 10L at anytime.
 

gwpharms

Well-Known Member
Now if i did that you wouldn't learn anything:lol: i dont know what your experience and education is but i will point you in the right direction, tell you what to research and look for. There are plenty of turn key systems out there where they will sell you everything and show you videos on how to do it. Im sure youve seen them by now. Keep in mind their understanding of molecular distillation is very narrow minded. But if thats all you want to know......
Dauhhhh drugs go here
If only chemistry were that simple. I might have saved myself years of schooling

This is a picture of my 12 liter still. About 3 liters in it here.You would want like a 20 liter or so to process that much. This might be aka a reaction vessel with a 3 neck lid. I prefer the old ball and socket joints for reasons you will discover later when you start breaking glassware

What you want to get and research is
Jacketed short path condenser/still head with viragex indents
The jacketed and indents is worth the money.more efficient. Dont get the $50 one.cheapest i know of that is still decent quality glass is laboy glassware. Buy direct from their site, comes on the slow boat from china so be paitent.it is good glass i have some laboy pieces. It will cost you about $200. 10 years ago it might have cost $40. Funny how these things appreciate in value when they are rediscovered by the world. You will also need to collect those fractions without shutting down to pull them out. That funny looking thing you see in all the pictures is called a cow reciever or a pig to some. Alot of people refer to the one that looks like teets as a cow and the one that looks like 3 light bulbs as a pig. You dont want the teets. It is not necessary to have the vacuum port on the receiving bulb since the condenser has one, but it cant hurt. You could use it for a manometer connection or something like that.
Of course you will need a mantle and a vacuum. Again i dont know what you know, but get a real pump not an oil sealed POS from harbor freight. Look into oil free diaphragm vacuum pumps or the wonderful aspirator. I use a brinkman recirculating aspirator pump for lengthy distillations and where solvent vapors might get into my pump. The recirculating pumps are much stronger and more efficient that a sink aspirator but cost alot more. Brinkman is about $800 a sink aspirator is about $50. But that $50 aspirator will out perform a oil sealed pump and last forever. No maintenance.
 

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gwpharms

Well-Known Member
Heres my pump. As you can see it is simply a pump head the rapidly puts water through 2 aspirator heads for twice the power. The resivour is to not waste water and its easier to maintain a constant water temperature which provides a more consistent vacuum pressure
 

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dabbindylan

Well-Known Member
What your max negative atmosphere you can acheive with the aspirator??? Brings me to another question could you vacuum purge shatters with a aspirator. Lastly have you done fractional distillation or only simple short path? Thank you any other tips are appreciative.
 

gwpharms

Well-Known Member
Of course its ideal for vacuum distillation especially where solvent vapors are involved. It is a real laboratory grade high vacuum pump. The guy's selling those kits with oil sealed pumps have never been in a real chem lab or read a book so they dont know about these things that have been around forever. It is completely assnine to use an oil seal pump to remove solvents for so many reasons.
This is a high end pump It pulls about 29.8inhg. About as close to a full vacuum as i could hope to get with this many miles of atmosphere above me.
A cheaper $50 one that connects to your sink might pull about 22inhg.
Still way better than habor freight pumps.Yes ive done some short path molecular distillations and collected the fractions
 

gwpharms

Well-Known Member
This is one of my oil free diaphragm vacuum pump. It pulls about 27inhg. Its up on ebay now. I use it for vacuum filtration. I have a few of them
 

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Fadedawg

Well-Known Member
I guess my real question is where can i get the glassware to do my fractions.. Links would be helpful. Im processing lots. 10L at anytime.
I've played with a Kugelrohr, but our biotech Pharmer Joe developed both our short path and molecular distillation processes, as well as various equipment.

A Kugelrohr would be way too slow for your needs, so suggest you contact [email protected] and I will put you in contact.
 

gwpharms

Well-Known Member
I thought the Kugelrohr did not reach high enough temperature? Or was it that it can not hold enough vacuum?

How much is the glassware and whom is it manufactured by? I mean the short path condenser and cow reciever
 

gwpharms

Well-Known Member
Either way, whats the boiling point i dont rember. 68? I think its the same as ethanol about. Under 29inhg it would boil at like 12 i think
I dont like the term purge much. Its misleading, inaccurate. Maybe purge under nitrogen would be a term ive delt with
What you are doing is a distillation. You bring a component to its boiling point where it turns to vapor and "escapes" and rises up out of the mixture and re condenses back to liquid when it cools. (In most bho purge oven systems this happens in your pump thats why bho guys go through vacuum pumps like socks) if only they would read a chemistry book huh?
vacuum is often misconstrued as being some magic poison sucking machine. Really all it is for is to reduce pressure and lower that boiling point. Thus protecting your heat volitiles from decomposing. Vacuum distillation to me always feels like a Rollercoaster ride. Maybe thats just because i have adequate control and monitoring of whats going on beyond what the "shat vac 3000" users do, im just more aware of the ups and downs
Everything in a vacuum is always changing. Heat ads pressure negative pressure removes heat vacuum pressure ranges changing boiling ranges. Its really a wild ride if you think about it, pandemonium in there. Crazy
What matters is that you know when you are vaporzing condensing and collecting. If you don't then you'll be one of these guys that thinks 8 days in the vacuum makes a difference. Weights and mesures are important too. How much do you put in? How much did you pull out?
I prefer vacuum distillation because its just more exciting i think. I vacuum distill my ethanol from mash under vacuum even though i certainly dont need to. Never gets old though, seeing temps drop and stuff boil at 10 degrees. I still envision myself on a rocket into space every time i turn the vacuum on and watch the guage climb. Like a kid
 

gwpharms

Well-Known Member
Yup its awsome. Still makes me giddy to think about. Done it a million times never gets old.
Not sure how much you learned about atmospheric pressure but the reason is that we have all this weight of the atmosphere putting pressure on all of earths molecules making them not move as fast and generate heat as easy. In space without this 80,000 feet of atmosphere pressing our molecules together, these molecules move much more freely generate molecular heat and boil. One of the first things you will learn about reduced atmospheric pressure is how a camper boils his drinking water and cooks his food at 100 degrees Celsius at sea level. While his hill billy cousin high up in the mountains at 10,000 feet boils his water at a lower temp and cooks his dinner a little faster
 

Fadedawg

Well-Known Member
I thought the Kugelrohr did not reach high enough temperature? Or was it that it can not hold enough vacuum?

How much is the glassware and whom is it manufactured by? I mean the short path condenser and cow reciever
As I recall, Aldrich charged around $6500 for the one we were loaned by a client to develop his process.

The Kugelrohr reaches both adequate temperature and vacuum, assuming an adequate pump. We used a 1405 Welch pump we had handy.

It doesn't use a cow receiver. It is two bulbs connected together without a rotary vacuum union, and the hot one is oscillated in the oven, rather than rotated.

Slick, but slow............. We moved on to a 5 liter short path and a molecular still of our own design. The still uses a Welch Chem Star pump.
 
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Fadedawg

Well-Known Member
Its very interesting that certain process can be done under just vacuum without heat
Technically, the definition of boiling, is when the internal vapor pressure equals the atmospheric pressure pressing down on it, which is about 14.7 lbs at sea level. As altitude increases, atmospheric pressure decreases. Here is a chart.
 

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dabbindylan

Well-Known Member
Crucial to distill hexane fully im aware of its carcinogenic property i try not to have any solvent left regardless of it bein more or less poisoning.. Impurity is impurity..im striving to make the cleanest meds using solvents that arent really normal to create... I. E new refinement process
 

gwpharms

Well-Known Member
As I recall, Aldrich charged around $6500 for the one we were loaned by a client to develop his process.

The Kugelrohr reaches both adequate temperature and vacuum, assuming an adequate pump. We used a 1405 Welch pump we had handy.

As I recall, Aldrich charged $6500 for the unit, sans pump. It doesn't use a cow receiver. It is two bulbs connected together without a rotary vacuum union, and the hot one is oscillated in the oven, rather than rotated.

Slick, but slow............. We moved on to a 5 liter short path and a molecular still of our own design. The still uses a Welch Chem Star pump.
I thought the Kugelrohr max temp was like 230 or 240? Making it a little to cool for thc
Also i thought i read that it doesn't hold a full vacuum, more like 26inhg. It lets pressure in or something? Or was it the inert gas it used?I suppose i could just watch the video on sigma aldrich and see. I have been aware of the Kugelrohr since it came out but it sounded like it was short of being good enough for thc fraction

I was more curious about the cost of " pharmer joes" short path distillation glassware he sells and what glass manufacturer he's using. Chinese glass like Chem glass, lg laboy, or is it something American made like ace kontes kimble pyrex
Why would he use a welch oil sealed polution pump? Would he like to trade me some glassware for one of my antiseptic diaphragm pumps or water aspirator pump?:lol:
 
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