Ethanol (Cold Ethanol Extraction)
Cold ethanol extraction is a common method for extracting oils from plant materials. Due to its polarity, ethanol is chilled to subzero temperatures to avoid extracting additional, less desirable water-soluble molecules.
In this application biomass is placed in vessel and cold ethanol solvent is pumped in. The desired oils are rapidly dissolved in this solvent. Unlike hydrocarbon solvents, ethanol has no risk of leaving toxic residual chemicals in the product, which is especially important if for human consumption.