This unit will be used for distilling ethanol out of the oil It is only a reclaim still so technically the cannabinoids in the oil which is left in the still will never pass through the Copper except for Turpines
@Champone I think cyclopath summed it up great here.
The problem isn’t the cannabinoids touching the copper, but rather what the compounds that will distill off with the etoh from the concentrate will do to the copper, possibly contaminating your ethanol and subsequently contaminating your extract that you re-use that ethanol for. I have had the misfortune of ending up with blue etoh when running a mash for my own personal vodka when I simply added baking soda to the wash in an attempt to achieve a more neutral spirit. Neither the baking soda nor the fermented wash touched the copper, but there was a reaction between the yeast nutrient I used and the baking soda which formed compounds that created copper salts, which then ended up in my ethanol. Copper salts being as toxic as they are, I decided to just scrap the ethanol and do a laborious break-down and cleaning of my still rather than try to clean up poisoned product. I have had the same blue ethanol problem when I try running too far into the tails, which probably means it is something with a higher boiling point than ethanol that co-distills that is pretty rough on copper. I wonder if that’s also what was causing the blue in cyclopath’s experience?
You can probably get away with using a copper condenser if you just distill off enough ethanol to move the product into a rotovap for finishing. Cyclopath stated that he didn’t have any issues with the color of his ethanol until he tried squeezing out the last of it from the extract. Hell, I use a copper reflux tower to re-proof my reclaim and I have had zero issues. But if I was going to invest the money into it myself, I’d rather just do it right the first time instead of having more expensive issues down the line.
How are you planning to run a boka under vacuum? My column is a boka and I’d love to be able to run it under vacuum, but being LM I figured it wouldn’t be possible to have any takeoff while running, which would make it inoperable.