Removing vac grease from distillate


#1

Hi, So I am wondering what people are doing about vac grease in the distillate. On my last run there was a leak on the condenser and cow joint. Some distillate flowed over the leak spot dragging some grease along.
I know how it got there, I know how to avoid it…
I am wondering how to remove it. Hoping just a second pass maybe would do it? Any help and input would be greatly appreciated!!! Thanks, Drive safe


#2

It will come out in a second pass.


#3

The grease shouldent be soluble in alchol.
what was the brand?


#4

Apiezon 501. On the second pass it looked like it clumped together and rode around in the boiling flask. Two other people said to would come out in second pass also. So that works for me.
Now I wonder what I would do if it happened on final pass.?


#5

just dont use grease then. I use ptfe rings and thc distillate to seal the joints.


#6

Apiezon 501 is great grease. Just practice not over greasing your joints. You should only see the grease come down halfway on your joint when sealing it. The more you rotate your flasks the further down the grease will go. And if anything you should be able to pick out the little bit of vacuum grease with a dab tool. There shouldn’t be that much getting into your product


#7

you know that stuff is really toxic when heated?


Apiezon_PFPE_501_Safety_Data_Sheet.pdf (153.4 KB)
300*c and the grease releases toxic gasses.
other tubes of grease read “may cause polymer fume feaver”

Apiezon_PFPE_501_Safety_Data_Sheet.pdf (153.4 KB)

simply “picking it out” will not do here, there are particles of the grease you cannot see with your naked eye.


#8

Wow, learn something new everyday.


#9

I tried those ptfe sleeves lol. I ordered a “supply” of sleeves for 14/20 joints for $17.

I got a total of one ptfe seal and placing it was such a hassle it simply was not worth it. I use the Apezion 501 product and it is like lotion compared to GE high vac grease I also use.

The reality is you can only minimize vac grease in a system and not eliminate it. If it is used on a high temp seal like at the boiling flask then the race is to complete distillation before all the grease is pulled past enough to break vacuum. Tricky when that piece is made uber hot. With proper care I found the trace amounts present to pose no problem save for one; My subsequent SPD runs typically need at least another 10°C to run the same batch when there is vacuum grease present in the boil. I obviously run micro amounts so a very tiny amount impacts greatly.

It is one reason I hate to run horizontal now is because it is painfully clear that vac grease contamination is impossible to avoid if you use it on a hot joint and pull vacuum down into MFP conditions. I can detect very trace amounts visually but also the rig runs much hotter to get the same job done.


#10

When you say use distilate, where are you using it I would think it would get to hot and then not work. I could be wrong please explain I would rather use that than grease if any kind


#11

Grease can contamanate your distillate.
Distillate is unlikely to comtaminate your distillate.
It turns brown as it gets heated for long peroids,
but it does the trick with a ptfe sleeve.


#12

Does anyone know how vac grease in distillate affects potentcy and testing? Could it be possible that the grease somehow obscures THCs visibility during testing? Correct me if I’m wrong, but from my understanding shouldn’t the grease come up on a test such as a chromatogram as a contaminant, visually seen as it’s own peak(s)?


#13

Don’t use grease. You can get plumbers ptfe tape at any hardware store. If you are going to burn it fix your vacuum problems. It can take some heat for sure and is fine to use properly and in your small town right now. 260C is okay for continuous use for PTFE.


#14

I use Apiezon H, on my hot joints. Like I told my buddy, I could let my mom put together my SPD with it and not have any leaks…


#15

I also use Apiezon and I’m aware of other materials for the same application, I’m just particularly curious about testing with said grease in products.

Thanks


#16

Its not going to come up on a contaminant test unless they test for it specifically. I havent seen any labs testing for vacuum grease at this point tbh.


#17

Be careful going anywhere near 260c on American made glass under vaccuum, 260 is what i was always told was the limit for glass under vac.


#18

#19

Really that high a temperature would never been needed in an organic lab under vacuum. I wanted to calculate what 260C under vacuum would be at atmospheric … but it’s above the np of probably any organic. However wrapping Teflon tape on the joints isn’t just for vacuum, it prevents a stuck or frozen joint, which is a real issue I’ve had lots and lots of times. So I mention the temperature really bc it’s higher than I’d ever go, a safe limit.

There are organic which are safe to distil at atmospheric pressure which boil above 260 however. The Teflon tape would probably not suffer too bad unless it went higher, but it does have this limit.

I agree you shouldn’t take glass under vacuum to 260 probably… however it seems to be that boro devits a bit higher and softens higher than that… but I love organic chemistry bc it’s all in a narrow range for the most part


#20

I’m sure another distillation would remove it… perhaps you can “winterise” it out… its non volatile and very non polar, but I haven’t used it in many years.