I run a CBD isolate and hemp processing facility in KY. We have started to accumulate a good amount of pentane and mother liquid. I am trying to find out what the best route to recycling the pentane and recovering the oil within it for further processing.
Is there recommended equipment for this that you guys use? If so, what kind of throughput on recovered pentane do you achieve with such equipment?
Any suggestion or help in obtaining the gold back from the mother liquid and recover clean pentane to reuse for more crashing would be very helpful. Thanks.
I was not able to find a topic on this when searching, so I hope this is not something that I am asking for the 1000th time and just too stupid to find the thread on it here.
Any still,rotavape or other kind of distillation device will work
The last bit will have to be done in an easy accessible still under vacuum
I have setup my cls as a still often and works well
Pentane you will need a low temp coldtrap definitely under vacuum
Thanks for the input. Know when I talked to AI about using a 50L rotovap they said it wasn’t suitable for pentane, talked to a solvent recycler place who said they would install equipment for it, but then said it was too low of a boiling point for their solvent recovery machine to work safely. I am thinking I may just go with two jacketed solvent tanks with one being heated with collection plate and the other cooled and do a passive recovery like I used to do back in the day with butane recovery. Haha
If your equipment supplier is telling you that a rotovap isnt suitable for pentane, then they either 1) dont know what theyre talking about, or selling you such a piece of junk that you shouldnt be buying it in the first place. Pentanes fine in most rotovaps or stills, just disconnect your vacuum and run it at atm
@Madwaxman Just make sure you regulate your vacuum depth and can watch to make sure the solvent condensation front isn’t making it to the top of your condenser.
We do our pentane recovery at atmospheric pressure, using a big steel steam jacketed vessel and heat exchanger to cool vapors. Is not perfect but no need for vacuum
build a stainless oil jacketed reactor- use TC fittings and PTFE gaskets. I can get you a parts list and quote and you can build it yourself for a fraction of the price of a pre assembled unit.
It eats there seals like crazy, i have a 5l i only use for pentane for that reason. Probably eats all seals, but you can and i do and have recovered pentane in an across roto.
I roto Pentane all the time, i dont leave anny valves open. Just pull a slow vacc(preferably with a vaccum regulator) and install a cold trap between roto and pump. Add sry ice slurry ofcourse. And set your temps accordingly.
Buchi has a pentane program supplied in their rotovap interface- it bases the parameters off the pot temp, I usually do it at room temp, it selects the chiller temp and vac depth. I usually drop the condenser bath to -15C
Thank you. What are recommended perimeters for Heptane recovery in the roto since it has 98 c boiling point/ use Vac on this one? Unlike pentane where can leave open to atmosphere? Thank you for your advice.
I’m working with mother liquor and incorporating it into some products and although the residual pentane is officially within acceptable range, I’d like it to be closer to zero, as I come form an ethanol extraction tradition and have a thing about stanky-ass residual hydrocarbons. If it had say 1 or 2 or 3000 ppms, how far do you think I could get that down in a rotavap at what temp for how long? Any advice on this would be greatly appreciated.
