How to complete CBD crystallization via HJLab Jacketed Glass Reactor?
Aug 23,2022 | Shanghai HJLab
- CBD crystallization is a long process involving a solvent (like pentane) and other steps such as stirring, heating, and cooling.
- Starting material is CBD that has been winterized and distilled. It should be clear (without the cloudiness indicative of contaminants). If it is still cloudy, it should be re-distilled until it is clear, as crystallizing oil with contamination will lead to poor yields.
- Extracted CBD is then added to Shanghai HJLab Jacketed Glass Reactor with stirring capabilities. Shanghai HJLab Heating&Cooling Circulator is also connected to the vessel for temperature control. In some cases, pentane is used as the solvent.
- To start the process, add three parts CBD to one part pentane into the vessel, turn on the stirring mechanism, and set the temperature to 45 degrees C (or 113 degrees F). Once the solution reaches that temperature and the oil has dissolved, lower the temperature to 5 degrees C and reduce stirring speed.
- The solution will cool and become more viscous. Once this happens (it’s called “precipitation”), adjust stirring speed to 120 RPM. This forces the CBD crystals to spontaneously form or ‘crash out’ of the pentane solution. Continually reduce temperature to fully crystallize the solution. Crystal growth depends on the temperature used, so testing is necessary to reach optimum crystal production.
- After the precipitation phase, the CBD crystals can be collected from the vessel, and the slurry removed. The crystals are then rinsed in ice-cold pentane to rinse impurities from the crystal surfaces. More rinses that will improve color but reduce yield.
- If the starting CBD distillate is 70 – 75% pure, crystallizing can produce isolate that has a purity rate of 90% or higher. If the starting distillate is less than 70%, the crystallized isolate will have 85+% purity. CBD crystals can be redissolved and then recrystallized to improve the potency even further.