Wondering about the effect of moisture in the cannabis prior to ethanol extraction and lowering the amount of sugars and other water solubles from the crude extract. Has anyone tried or does anyone have in their preprocessing heating up their cannabis to remove the excess moisture, volatile terpenes, and decarbing the THCA? My thought is when using anhydrous ethanol the moisture in the cannabis biomass will be picked up by the ethanol and also pull out water solubles. Does anyone heat up their cannabis prior to extraction or is it negligible?
Is anyone actually using anhydrous EtOH on a large scale?
If you are, how are you breaking the azeotrope after you’ve recovered your EtOH to ~96%? This is going to be a huge bottleneck in any system I’d assume - making any system designed to run on 100% EtOH rather impractical.
I think the fact that most people are only using 96% EtOH would make the water in most flower pretty insignificant. I did have some nasty problems one time trying to extract wet trim which had been soaked for making ice hash - was pulling fractions in the rotovap when recovering that one.
You will definitely be pulling water solubles using EtOH at room temperature, or even using cold EtOH 96%. I’ve often noticed thin layers left coating the inside of flasks which are water soluble but insoluble in EtOH, IPA, Acetone, pentane and hexane which will separate after a solution sits for long enough.
These are different from just the regular water soluble lipids which separate at colder temperatures, as these will drop out of solution at room temperature if given enough time.
All that aside, given most EtOH extraction simply ends up as distillation feed, and many(most?) people will boil off solvents and volatiles (and anything else which will boil below 140°C) before a scrubbed oleoresin even makes it to the boiling flask … I don’t know how necessary a decarb step really is before extraction.
Before extraction seems pointless unless you’re drying material with huge amounts of water in it at the same time. Though my experience is with EtOH 96%, so I can’t comment on whether this may offer advantages in heptane (or even anhydrous ethanol) extraction.
Crude destined for distillation (most alcohol/alkane extract) will be decarbed before loading or during distillation anyway, and for the rest, THCa seems to be the more desirable compound anyway (no-one wants d9 dominant hydrocarbon extract unless they too are using it as distillation feed - in which case it’ll be decarbed before loading or during distillation anyway).
When I was running large scale ethanol extraction we recycled the ethanol with no problems. I have heard that 95% EtOH is a better extraction solvent than anhydrous, but haven’t tested this myself. The ethanol I was recovering on smaller scale cold ethanol extraction was 95% or better when I checked it with a hygrometer.
One company I was at had a license to purchase specialty denatured alcohol with ethyl acetate and it seemed to work well for cold extraction. However, the completely denatured alcohol formula with heptane doesn’t require a special license.
Please use caution with heptane denaturant. There are more problematic health effect with long term exposure to heptane vs ethyl acetate. The metabolites of heptane are neurotoxic.
Drying and Decarboxylation prior to any CO2 extraction is crucial for better extraction efficiency and shorter run times.
I’ve been looking into the cascade sciences dry and decarb oven but don’t know enough about it’s performance and durability - would appreciate any feedback from someone who has worked with the unit.
I can see if I can find a reference customer for you. What I can tell is is that I have sold a LOT of them in the industrial space for curing, drying and baking of everything from golf balls to rocket parts with sterilization of lab glass in between. They move a ton of air and the ways the holes are arranged and sized optimizes movement across the shelves with even distribution from top to bottom. Customers have responded well to the mesh bags and I am impressed with the amount of material that can be run in one batch. If you figure 1.5-2lbs per shelf, 10 shelves per oven you have a nice throughput.
A reference customer would be awesome - thank you!
I hope we can fit more than 20lbs of finely ground material in per run as the facility we’re working with now needs to process 10,000lbs+ of cannabis biomass per week.
It works great for what it is. The temp stability over a normal oven is really nice. Works great for flower or extracts, and is a good way to minimize loss transferring jars without worrying about over cooking.
I have gotten around enough in this industry that I don’t think I can hear someone say “10,000lbs a week” and keep a straight face. But I guess 35 ovens and 350amps of breakers should do it.