Hey everyone, I’m fairly new to the distillation process. I recently bought a 10L system from USA labs, and it seems like I’m running everything properly but for some reason I cant get cbd to produce above 40%. I have been running the short path around 250 microns, and use krytox grease to ensure the short path isn’t having any leaks. In the 1st fraction I hold a temperature around 140 degrees in the distillate head for about 30 minutes. After about 30 minutes I increase the temperature to about 180 degrees Celsius in the distillate head and hold for about 30 minutes in the 2nd fraction. Then I bump up the mantle temperature again to get a temperature reading around 200-210 degrees Celsius in the distillation head to produce the sell-able distillate. When the temp in the distillation head is 200-210 degrees everything is now in the 3rd fraction, (the larger fraction). I make sure the oil is changed every cycle, I have the right amount of vacuum, I even 3rd party tested the crude to make sure I wasn’t getting bad crude. Can someone please tell me what is going on?
ID 1 = 1st fraction held at 140 degree’s Celsius (distillate head temp)
ID 2 & 3 = 2nd fractions held at 180 degree’s Celsius (distillate head temp)
ID 4 & 5 = 3rd fractions held at 200-210 degree’s Celsius (distillate head temp)
ID CRD = is the Crude to double check the cbd contents.
So to be clear you’re stating that your distillation head vapor temp is 140c at the first fraction?
If this is correct this is likely your problem…you’re waaaaay too hot. What is the temp of your solution in the boiling flask?
I generally pull cannabinoids between 135c-180c with the vast majority residing between 135c-160c. This is with a vac depth of only 400-600 microns and a boiling flask temperature between 190-205c
Yes distillation head temp is at 140c in the 1st fraction.
What temp should it be at for the 1st fraction?
In the 3rd fraction the mantle temp is generally around 190-205c and the distillation head vapor temp is around 202c. I dont understand how I could get less cbd. like 20% less. I will literally pay you if you can help me figure this out.
Depends what solvent you’re extracting with, but give these a shot. Keep in mind these are rough but should give you a very good place to start from.
Boiling flask temp:
80c (solvents)
145c (light volatiles)
185c (heavy volatiles)
190c-210c main body
Distillation head vapor temps:
20c-45c (solvents)
45c-90c (light volatiles)
90c-130c (heavy volatiles)
140-180c (main body depending on system and material used)
I collect my main fraction starting around 175 vpt then hold between 180 and 185 vpt. When the color in the vigs darkens or I’m about 80% through my crude I switch to the tails. I then crank to 205 to 210 in the bf or around 190 vpt and let the tails collect. From what you’ve said I think you are losing CBD to isomers because you’re going too hot for too long. Vac is also a touch high. Try apiezon 501 grease. Krytox is garbage. If you’re using gl connections make sure to use thread tape, preferably the PTFE impregnated type.
What is the standard time for running a short path? Also what do you mean when you say losing CBD to isomers? We recently just ran the short path again so this crude has been ran twice. We are using hose clamps to get a better vacuum. Maybe we should take those off?
In the presence of heat and an acidic catalyst, cannabinoids are prone to undergo a chemical reaction called isomerization, wherein the product of that reaction is an isomer of the starting compound. An isomer is defined as two or more compounds with the same chemical formula but different molecular structures as well as different properties. Thc and cbd are isomers. @Sean99
Hey @ScoobyDoobie thank you for the quick and detailed response. I found other threads saying that you can convert CBD to delta 8’s and delta 9’s. I have not found a way to convert it back. Is this possible? Also does the PH level of the crude play a role in the problem with isomerization in our distillate? Should we decarb the crude in the beginning? Can we do this after we distilled already? Here is a link that I found helpful in explaining how to separate through liquid to liquid extraction, its a little bit over my head.
Ph of your distillate has everything to do with isomerization reactions occurring. You want your crude to be neutral PH before you put it into your boiling flask. Do you use any adsorbents in your crude production?
I dont personally know much about the THC to CBD reaction, I’ve just heard that it can be done. And that you would be a rich man if you’re able to figure it out.
You will want to make sure your PH is neutral before you decarb because acid + heat = isomerization. Are you using a wiped film or an SPD? If your using an spd you will want to decarb before you distill. But if you already distilled once then that would have been enough heat to decarb your extract.
How to we test our crude to have a neutral ph? Also we have already ran several batches of crude, with our SPD. It seems as though we have decarbed the crude on accident by running it in the short path without testing the PH level. We have ran the crude initially and then re-distilled that batch again, and the cbd content went down even further. Is there anyway to reverse what we have done?
