A rotary evaporator, also called a rotovap or rotavap, is a specialized piece of laboratory glassware used to gently remove solvents from cannabis extracts. It works by rotating a round bottom flask containing the extract under low pressure, while applying heat to encourage evaporation. The evaporated solvents are condensed and collected in a separate chamber.
This allows extract artists to separate and isolate desired compounds from the extract by evaporating away everything else under precise temperature and pressure control. Rotary evaporators prevent scorching heat from degrading delicate compounds like terpenes. The artist can tease away minute contaminants over time, revealing an exquisite, concentrated essence of the plant's most desirable elements.
Winterization and molecular distillation of concentrates utilize rotary evaporators to remove residuals, chlorophyll, lipids and other undesirables accumulated during extraction. The apparatus can also concentrate compounds by evaporating excess moisture and solvents. When crafted skillfully on advanced equipment, rotary evaporation can transform crude extract into a refined, sophisticated concentrate.