How do you get to-70 for so long? I have a chiller that goes to -10. And for winterizing I use dry ice baths that go down to -70 or so at peak. But dry ice is my worst enemy
Thereās freezers that do -70+ and liquid nitrogen, and chillers.
Lots of options
Scavenge the web,auctions,and craigslist for a ultra low freezer they are tha bomb
I find them regularly for around $1000
They make every thing so much easyer
Realy!!!
O scooby i scavenge auctions here in europe so diffrent playground
But all freezer i have including the revco Where less than 600ā¬ each i collect them dry ice is hard to get often an hour drive or more delivered always 20% less and at 4ā¬ a kilo iT s a pain
I have a dry ice maker for the shortpath coldtrap and thats iT
All biomass go under vacuum in the tubes
In the freezer 36" tubes lenght
And then blast away
I also have a -40 freezer to pre freeze iT all so the ultrafreeze doesn t get to stressed
Service is not often done on a cascade system all service i do myself
Keeping the heat exchangers clean with a vacuum cleaner and Some wd 40 on other parts
Scraping off iceforming with a plastic spatula on the inside once a week and defrosting When neccesary
And last Keeping the sealantt rubbers of the door clean and sprayed with a ptfe lubricant spray
As other have said an ultralow freezer. We picked up a used one, not sure what we paid for it though.
So update!
It happened again. Had it under vacuum at 80c or so. I think this stuff has some moisture stuck in it and itās forming a methanol/water blend thatās sucking up some scum and terps LLE style.
Iāll boil it down and test, but that seems like the most likely scenario?
How are you removing the solvent post winterization?
Rotary evap under vacuum
What vac depth and temp? Even a perfect rotovap will leave solvents behind, but even more so vac and temp are less than ideal.
Got it up to 28" and 100c before I decided to put it in a sep funnel
Hmm, very weird. Thatās actually harder than we run or rotovap, so I donāt think it would be solvent.
It doesnāt freeze either.
Iām still learning towards a water, methanol, terp, scum, fat emulsion.
I think thereās some thc in there as well. But not much. It has a sticky feeling when you rub it in your fingers for a while
Itās only started happening when I switched my winterizing solvent to methanol. I think maybe itās something to do with the lower boiling point of methanol compared to ethanol.
I find this often this layer and i wonder If methanol is. Not an azeotrope but i think iT is a water attractor
Example all tools etc used for bho i rinse in the collection pot after use with methanol If i then pour iT all in a pyrex plate all methanol Will evap off but Will leave me a 10% by volume layer of what You describe and the oil as a separate layer on the botom of the pyrex
The methanol Iām buying says 99.9% methanol and itās from the hardware store. Do you think itās the 0.1%?
What @Roguelab describing is a result of water molecules being condensed inside the alcohol solution as it evaporates. You will gain a significant amount of water in this way but I know you use a rotovap so that shouldnt be the case, you dont evaporate in the atmosphere so theres nowhere water can come in at those amounts.
Methanol is very hygroscopic like erhanol.
I live in a remarkably wet climate (BC) so thereās certainly opportunity for moisture to come into the picture.
The lack of freezing is still puzzling me. I guess thereās minimum 20-30% methanol still in there.
What have you tried so far other than freezing it? Does it boil when you vac it still?
Also this is unrelated but I think u guys will enjoy the read.
https://www.quora.com/What-has-a-higher-IMF-methanol-or-ethanol