Stinky Distillate

Hi everyone,

in our kitchen we are making a CBD distillate using a short path distillation system. So far it worked great. We have made it using ethanol and got crystal clear distillate out with nice smell. When we switched to isopropyl alcohol the distillate became darker and stinks at the end. The short path does not separate the tepenes anymore. So the green brownish, slimy and stinky terpene fluid is not comming out anymore.

Does anybody have an idea if this could be isopropanol, or any other idea why our distillate stinks at the end?

Thanks!

You didn’t accidentally use denatured alcohol did you?

I’ve never used a short path. From all the research and experience I’ve had with alcohol extracts though I believe the isopropyl should have evaporated out cleanly without leaving any residue.

I do a thin film evaporation on my qwiso and get a full evaporation every time.

You mean denatured ethanol or isopropanol?

So, in the beginning we used 99% ethanol, but after recyclation we used the 97% one.
We now use 99.9% isopropanol, and then we recycle it and use the recycled one.

Thanks for a fast reply

Julia111 said:

You mean denatured ethanol or isopropanol?

So, in the beginning we used 99% ethanol, but after recyclation we used the 97% one.
We now use 99.9% isopropanol, and then we recycle it and use the recycled one.

Thanks for a fast reply

Click to expand...

I was asking if you accidentally used denatured ethanol. I buy my ISO at the drug store and 91% iso is basically right next to the denatured so if I wasn't paying attention I could see accidentally grabbing the wrong bottle. Just my first thought on it.

One difference between ethanol and isopropyl, is that isopropyl is less polar than ethanol. Did you winterize it before short path to remove the non polar plant waxes?

What is extracted during short path distillation is a function of temperature and vacuum level. What temperature and vacuum level are you running?

Vacuum levels are as, or more critical than heat, as it takes more heat at higher micron levels, which darkens the extract. You should be below 20 microns. The MERCK Index gives 200C at 20 microns as the boiling point of THC.

Pics of setup
What's mantle temp, head temp, vacuum level?