Difficulty with purging

Hello I have been producing THC oil and when I am finished with it I use my distillation rig that I have to reduce all the solvent possible then I re constitute it in ethanol to remove the remnants of the first solvent it is in. However I have an extraordinary hard time with my final purge getting to the acceptable PPM.

My stuff starts off as perfect as can be will look gold in small quantities and very translucent orange or red. However when in bulk I cannot seem to rid all the solvent and keep that quality. What I have resulted to is setting it up on a stir plate with a heat gun propped up blowing over it. While I believe this fully removes the solvent it absolutely darkens the oil to near black. When taken up in a dart it will still look reddish but I have had it near perfect gold and in the acceptable ethanol PPM.

I have never found a sure fire method. And although I lack a lot of equipment I was wondering if anyone could give me tips on exactly what to shoot for that would give me the best results. I was thinking a roto-vap is all i needed but from what I ahve seen most distillers start with a rotovap for a beginning process. So that must not be the only thing to totally rid solvent. Although it would help me out with the bulk of it.

Then there are vacuum ovens which I’ve never looked into but that’s the only thing I can picture working. Is the heat gun blowing over the oil turning it black in the process certainly degrading the oil?

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Im confused. Are you putting your crude into a rotovap or spd?
What is your end goal? Distillate? Or full spectrum oil for darts?
A vac oven will help remove solvents.
Are you extracting with ethanol?

The heat gun is for sure nuking your color.

Edit. I have never gotten 100% of the solvent out in a roto

The oil suspension I am using spd to remove the bulk of the solvent then once from there I have tried a food dehydrator which does nothing then the heat gun which removes the solvent but at the cost of the color, thank you for the confirmation on that.

My end goal would be ideally keeping it raw because I am processing about a 100 grams at a time and stocking piling it up.

I am using ethanol as a stripping solvent which I realize now I shouldn’t have done. Because the thing I am following said use toluene to rid it but I elected to buy ethanol because I thought trace elements of that would be more acceptable. Now I realize that anything under the right PPM would have been okay.

But taking your word on the rotovap not being the answer to my problem I should think about just getting a vacuum oven. Which I assume degrade the color a lot less than the stupid heat gun which i why I was hesitant about using an oven.

Wait your using a spd? Post a pic something isnt adding up.
So your end goal is distillate correct?
Even bad oil looks good suspended in solvent for the most part. Could just be dark oil.

Sounds like he’s using a short path to recover eoth extract or crude… Maybe

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Yes my end goal is distillate I’ll post some pics. I am using the SPD only to reduce or recover solvent I don’t actually distill the THC oil ever because I don’t have a chiller.

You dont need a chiller for spd. You need a heater. And thats cheap.

So whats the problem with your crude being dark? I only used to run black stuff in the spd. Once you distill it youll have a good color

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Here are some pics of the set up. perhaps if I properly distilled I could avoid even needing to use the oven. Not to mention the purity of my stuff would be way higher.

Also I think in the pick I replaced the distillation head with a massive condenser but I have the thing it came with as well.

So you’re currently stockpiling crude, for eventual distillation?

You should easily lose the last of your solvent during decarb. So you’re over thinking the problem I believe.

I also believe I heard you say you were extracting with a solvent other than ethanol, then resuspending in ethanol. If you’re going to that trouble, you might as well chuck it in the freezer and winterize while you’re in ethanol.

See Trouble with new 10l short path. for “chiller” needs


I’ve left out more details on what I am doing. However seeing some of the top threads I don’t think it’s much of a secret as I thought.

Really what I am doing is converting CBD isolate to THC. So the initial solvent is the one where the reaction happens then I boil that down and resuspend in ethanol just to remove the solvent again in an attempt to clean it up.

+1 What he said☝

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well then.

Strangely enough, that changes the advice…

@Slabby is on point

and you should absorb the threads currently detailing that super secret turns hemp back to cannabis after the fact alchemy you thought you were keeping from us :rofl:

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you wont need a vac oven and i heard future say t41 in the boiling flask makes d8 thc with cbd

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The best take away at this point is look into doing distillation which apparently doesn’t even involve a chiller but a warmer. And that linked thread made it seem like a warmer doesn’t even need to be that precise?

I’ve had different batches tested and my average is 77% delta 9 thc with my highest being %84 I think if I actually distilled this crap I could be in the 90s. I’ve never had delta 8 or anything else detected for that matter.

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Your converting to d9? Can you elaborate on that?
Ya you dont need a precise heater. Hell a 5 gal bucket a sues vide cooker and fountain pump will work.

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Yeah, a sous vide is probably a better tool than the bucket heater.

They have a thermostat but it fails to protect an aquarium pump so the pumps tend to only last a couple of weeks in my experience.

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Yeah I’m taking CBD isolate which I had tested at 99.99 then the second kilo i bought came with results over 100 which I’m unsure of how that happened.

But then I take that isolate suspend it in a solvent add acid and it converts to d9.


Ya multiple pumps on hand is a must

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Which solvent and acid?

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The initial solvent is DCM which is pretty bad stuff, I’ll have to go through my history latter to make sure this doesn’t come back to me somehow. But I don’t think I’ve ever had trace amounts of it. I’ll show some results.

Also I should have said in the beginning I didn’t know it would screw up the advice. I appreciate the help.

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