Soxhlet extraction devices are ingenious inventions for the continuous extraction of sparingly soluble solids with a volatile solvent. The flask and extraction solvent are heated and the vapors rise up the outer sidearm until they reach the water-cooled condenser. The condensed solvent drips into the Soxhlet device and onto a porous glass or paper thimble containing the material to be extracted. When the level of the condensate in the extractor rises above the inner U-shaped sidearm, it automatically siphons the solvent and dissolved material into the lower flask. The cycle then repeats itself.
Typical uses for Soxhlet devices include extracting fullerenes from raw soot (using toluene or similar solvents) and the determination of fat content in food or feed samples (using hexane as the solvent). These are also great for the extraction of essential oils.
The following are complete soxhlet setups. Click on any of these to get a more detailed description, choose a size, or to find component parts.