Just did a distillation of crude from cryo ethanol extracted trim. Started with 464g of crude (not decarbed, some residual ethanol). Heads totaled 23.37g, mains totaled 314g, tails totaled 18.58g. Didn’t weight out cold trap contents, but it couldn’t have been more than 5mL, which leaves ~103g in the boiling flask (not accounting for the loss of CO2 from decarboxylating). Mains yield was 67.7%. Is this egregiously low? I’ve been told 65-75% is normal yield for 1st pass from crude. Is that accurate? Is there a rule of thumb for the ratio of main body to heads to tails to remains in boiling flask? I saw the main fraction start to darken up, went from a pale yellow to darker gold towards the end. I didn’t swap flasks immediately and collected the darker golden stuff with mains b/c visual estimate of amount in flask seemed low. Eventually swapped over to tails, but I think based on color my main body and tails overlap considerably. Had I swapped earlier my mains yield would be even lower than 68% which I think is already low, so I dunno. Now that I think about it, since my crude starting material wasn’t decarbed when I weighed it am I getting what I think is a low mains yield because I’m including the mass of CO2 in the weight of starting crude? Just thinking out loud now, sorry.
Thanks!
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Did you test the starting material? What you put in will effect what you get out. 68% is a pretty good first run yield.
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You should always purge and decarb before spd.
I’ve seen a few instances where the crude bumped all the way into the cow rf.
I’m betting at least 1/3rd of the crude was pre-decarb stuff (residual etoh, and co2)
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Nah didn’t test. Testing fees are killing us so we’re shaving costs where we can. I hate it. Would love to have more data.
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Lol, I’ve bumped it straight through to the cold trap in the past on stuff that was supposedly decarbed.
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I kinda do. What I did this time was out of 2L rotovap, transferred to tared boiling flask (where I got crude weight), and then decarbed on mantle without vacuum or distillation head (just open flask).
I’ve been doing it this way b/c I have a good heat controller for the mantle but not a good hotplate w/ probe. Once the crude is up to 140C for a bit and smooth I assemble the rest of the SPD and pull vac. Don’t usually have an issue with bumping. Am I overlooking anything? Thanks! Feeling a lot better now. Didn’t consider the fact that my starting weight was not decarbed until now and have been feeling like I suck at this for getting what seem to be low yields compared to a lot of guys on here.
I definitely going to start getting starting weights post decarb now
That’s a decarb. I do it the same way. 5l rotovap, pour into 2l spd bf. Purge and decarb at 140c until a nice smooth lake of crude. Attach spd glass and start running.
I pull 75% of 1st pass 93%+ distillate from my crude.
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The 75%, is that from the weight of decarbed crude right? Not crude out the rotovap? 93% on 1st pass is great. Nice job! What is your vac depth during mains and what is your typical vapor temp range for collecting mains? I’ve never hit 90% thc or even total cannabinoids on 1st pass.
I think your yields sound fine. Sounds like a good distillation.
I have been sending a lot of tests in latet and I’ve noticed that the cannabanoid profile between the light colored mains is about the same as the darker tails… just thought I would share
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Good to know, thanks for sharing!