Hey, I noticed a previous post involving a giant fuge style system that someone had posted, that appeared to run under vacuum?
I was curious if anyone’s built anything to just straight up evaporate cannabanoids from biomass?
Maybe some kind of tube with an ever warming nitrogen feed. Pulling off terps first, then slowly warming up to 200c+ or something under super deep vac. Maybe eventually killing the nitrogen feed once the system is warm enough.
I think there’s an Israeli company maybe doing something of the sort for inhalers if I remember correctly?
Seems kinda time intensive perhaps? And probably a marvel of mechanical engineering for proper flow pathing. Aaaaand I can’t imagine it would be faster than just using a solvent like ethanol… But… If you did run it under tight enough parameters, you might just end up with a high quality distillate straight from the plant.
Has this been covered in depth before? I feel like I’ve read most of the site and it’s only been touched on.
I can’t imagine why you wouldn’t be able to lyophilize cannabinoids directly. It’d probably be slow as hell though and you’d need a system capable of pretty deep vacuum. You’d also probably pull a whole bunch of random other junk because you won’t have excluded any compounds based on their solubility parameters like we normally do in the extraction processes.
sublimated? no, but what youre describing isnt sublimation its just evaporation. I worked at the Israeli company that has a Vapor Capture Technology extractor, kind of similar, just vaporization then extraction
It would be sublimation as long as your material stayed cold enough to stay under the eutectic point for each compound being distilled. There will be some compounds where this isn’t possible and they will boil conventionally. What’s cool is that you’ll get a different order of compounds subliming than you would distilling from liquid based on different eutectic points/latent heats.
The reason this will be slow is your fractions will all have to sublimate completely as you ramp otherwise it’ll get all mixed up as you overshoot and some compounds become liquid before vaporizing. The reason I mention deep ass vacuum is also that you’ll probably start to burn/degrade/carbonize some stuff on your way to the cannabinoids fraction unless you can get the temperature low enough by pulling mega deep vacuum.
The upside is that the fractions should be very very crisp because you’re much less likely to codistills from a solid than a liquid.
I did some research on a process like this. Vapor Distilled already has a patented process that uses an ethanol spray condenser to collect distilled cannabinoids.
With the startup I work for we built a high temp screw conveyor “dryer” that went up to 200 degC + and allowed continuous contact between an air stream and input biomass. Seemed to me the collected oils had some nasty degraded/oxidized products. Unfortunately our company had to pivot to a more readily sellable process before we could really investigate the ‘hot air’ process. (Yes we used air, N2 is probably requisite.)
One major drawback of using screw conveyors for a large throughput process involves heating… one can’t scale to larger flow rates (i.e. larger conveyor diameters) without confronting a harder heat transfer problem. One way to get around it would be to use steel shot like so:
But then the process layout needs a bucket elevator and get pretty intense:
Above process is from “Fast pyrolysis of lignocellulosics in a twin screw mixer reactor” by Henrich et al 2018.
Still I think a continuous process may be doable… New Black Technologies is a microwave pyrolysis company that I’m pretty sure has tried pivoting to hemp. Neat thing about a large scale continuous ‘direct distillation’ process is that it could integrate well with higher temp processes like torrefaction and pyrolysis that may use the spent biomass to make value added products.