Fractional distillation

dabbindylan said:

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

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dabbindylan said:

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

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gwpharms said:

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?

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Fadedawg said:

You are correct on maximum temperature without reprogramming, but that is more than adequate, with adequate vacuum, as evidenced by the undeniable fact that it works. I know of one lab supplying Clear, simply using a row of them.

You are sorely mistaken regarding maximum vacuum. With no rotary seals, vacuum levels are dictated by the pumps capabilities.

The Kugelrohr works for the C-10 thru C-21 fractions, leaving behind the higher boiling point ones.

If you will send me contact information at [email protected], I will be glad to put you in direct contact with Pharmer Joe.

The Welch 1405 was available for free and did a good job for what we used it for. As it isn't in contact with the product, pollution isn't an issue.

Joe used the Welch Chem Dry on the equipment he built. Any issues with that?

We use Welch 2052 diaphragm pumps on our ovens. I also did early development work using GAST diaphragm pumps for solvent recovery, but they are limited on maximum vacuum and diaphragms fail, so moved on.

I gave up on water aspirator pumps after noting that they are both limited to about -28.5" Hg vacuum levels and they pollute the water stream. We have several plastic and metal ones lying around unused already.

They can be hooked up to a sump pump in a closed tank, to keep the pollution contained, but that adds equipment.

We use an air aspirator venturi pump on the Mk IVC/VC Terpenators, which will pull to -29.5" Hg vacuum, but is extremely noisy without mufflers and uses 22cfm of air to operate.

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gwpharms said:

The brinkman recirculating aspirator pump pulls 29.5 or better depending on water temp. I keep an imersion cooler in there. About 10 degrees is perfect. Then it will flirt with 29.7 or 29.8
Its obvious to tell when the water resivour has taken on solvent. Thats whats its there for, like a filter or a trap. Its simple to drain and refill while on the fly. Waste water can be properly disposed of if environmental regulations are an issue or concern. Or just go down the drain.Not so much regulation in the cannabis industry yet. Epa and fda haven't gotten their claws all the way in yet.

I can have a conversation across the room with the brinkman running. Sounds like a white noise maker people sleep too. It actually gets quieter as pressure drops and ends up a barley audible hiss.
I have built one with a bilge pump a bucket and two of those plastic aspirators. Thats noisy. Pulled 29.6 inhg though
I wish gast pumps were better as they are made just 30 miles away from me.

Gast pumps are not suited for lengthy distillations especially when solvents are involved. There typically 1 head and weak. They use rubber diaphragm. Thats no good. Have you ever tried a antiseptic sprayed diaphragm pump with ptfe diaphragms? There is alot of diaphragm pumps on the market that do not have these features and people get dooped into buying one and developed a negative opinion.
I mean that i understand welch oil sealed pumps polute the environment of the lab through exhausted fumes? like a car. but im assuming yours is vented to the outdoors or not in the room if that is the case.
What i dont like about them beyond that is the fact they condense solvent in the oil requireing frequent oil changes and causing frequent failure.
Also every time you change the oil they start loosing performance as soon as you trun it on and start condensing solvent in your motor oil
Only pharmaceutical labs ive ever seen oil sealed pumps in was in India

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gwpharms said:

View attachment 3799025 Correct. Has to be 10c to beat 20mb thats one pump head too i belive
have to use both heads connected in a Y. Like having 2 pump heads. 5mb no prob
Water flow rate and temp determine how low it can go.
At least mine does maybe im special. Just sharing what ive seen in my experience. It definitely does the job. The guy that sold me on pointed that spec out and said you need to have a cooler in there to get better than 20mbar. I believe the manual states that as well but i haven't seen that in years
Here is the cole palmer. It has fater flow rate pump so it can do better with 20 degrees up to 40 degrees. But same as with the brinkman lower the water temp the lower the pressure

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gwpharms said:

Ok now you got me curious.your talking finer incraments than i can read analog. Had to set up a experiment.I borrowed a digital from my mechanic friend. Expensive toy. $500 he mentioned that several times
Reads 0.0000 incraments of inches mercury absolute
0.00 tor /mm mercury
O.000 kpa
Psia 0.00000
Plus a bunch of others


Setup a simple distillation
1000ml 3 neck fine capilry septum claisen liebig vac take off.

Hooked up nitrogen with the hoffman on the hose to regulate. Nitro will add positive pressure so Also dropped a stir bar in to try both ways. (I Have stir on my small mantle not on the 12liter glascol)

Chilled resivour to 1 degrees. Added 500ml etoh. Did not use heat for this experiment but i know that would change things if i was

Heres what i get with nitrogen bubble
Mmmercury torr .010
Without nitro and capilry needle pulled .002

Micron 100 with nitro
10 without
Psia .0019 with nitro
.00018 without nitro

Inches mercury with nitro
.00393
Put an :"ish" on all that

Ill stop there but i have more written in my note book. I may have some numbers and things switched around here. Reading from top of the claisen not from pump. Kinda doing this in a hurry so may be an extra 0 or decimal misplaced. but from the numbers you see could i distill thc at 240 or less? ( i think its 240?) I have to talk to text here. Fat fingers and old eyes
If those numbers arent good enough i would probably just get a second pump and connect them together in line or series or whatever.Still beats a $3000 polution machine in my eyes.
Lol cost as much as a used car and uses more oil
I have not short path cannabis. We'd have to move this to erwid for what i have

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Dannoo93 said:

Hello all i recently got a 2l short path distillation setup at work. i am still confused as to how much vacuum i pull and at what temperature thc starts to boil off.. ive been at 220c with very little vacuum . any information would help boss man wants some clear put out
Thanks in advance

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Fadedawg said:

High vacuum is crucial. You need to be in the low micron range. 220C is the upper end of the first distillation, starting closer to 185C.

Pharmer Joe takes a second run at the black waste fraction up to 300C before pitching it, but the product is dark and requires further processing.

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Dannoo93 said:

So almost full vacuum then my pump can get to about 27 inhg

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Dannoo93 said:

185c is when the first set of terpenes start to frac off if I've read correctly. and then move up in increments of 10c. may i ask what temp thc starts to frac i thought that was at about 220-225 Celsius. ive read a lot of the skunk pharm info and as much i can find on the internet but this is so new and secrative compared to like bho or co2 extraction.

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