Wiped-Film Molecular Distillation
Pope Wiped-Film Cannabis Distillation & Extraction Equipment
After extraction and winterization and decarboxylation, THC, CBD or Total Cannabinoid in extract is typically in the 60 to 70% purity range. Starting with these feed percentages, you can expect purity from mid-80s to mid-90s in percentage after two still passes using Pope distillation equipment, depending on starting material quality. Yet greater distillate purity is possible via re-distillation of distillate.
Pope Wiped-Film Molecular Stills (WFMS) are a special type of short-path, molecular distillation equipment. These are continuous mode systems, as opposed to batch vessel distillation apparatus. The diagram below of the cannabinoid purification distillation process illustrates the means of this technology and shows the flow of the feed material and the separation of component fractions within the equipment. The same purification distillation process can be used for multiple cannabinoid compounds including CBD purification and THC purification.
Feed material is delivered from a feed flask into a cylindrical evaporation section, having heating, on the outside, (either electric resistance or circulating hot fluid jacket type), and a diagonally slotted wiper mechanism forcing liquid around and downward in a thin film on the inside. In the center of the body is a closely positioned internal condenser, providing a short path for vapor molecules traveling from the heated surface to the condenser surface. For cannabinoids, the internal condenser fluid must be kept elevated (~70°C) to prevent high viscosity or freeze up of THC, CBD and related components. During the journey downward, lighter (lower boiling point) fractions of the liquid begin to vaporize, move to the internal condenser and condense, falling down as a liquid into a well that captures and separates the distilled liquid (cannabinoid) which flows into a receiver flask. Heavier residue material (Chlorophyll, salts, sugars, heavy wax fractions) does not evaporate and instead travels the length of the still body and flows into a different receiver flask. Because of the optimized Pope design, this all happens within a number of seconds, and under vacuum-lowered temperatures, thus minimizing any possibility of product degradation.