1. Dr. Muhammad Qasim Hayat
Course: Medicinal Plants Technique: Soxhlet Extraction and Rotary Evaporator
Dr. Muhammad Qasim Hayat

2. Soxhlet Extractor
A piece of laboratory apparatus invented in 1879 by Franz von Soxhlet.
Originally designed for the extraction of a lipid from a solid material.
However, a Soxhlet extractor is not limited to the extraction of lipids.
Typically, a Soxhlet extraction is only required where the desired compound has a limited solubility in a solvent, and the impurity is insoluble in that solvent.

3. Parts of Soxhlet extractor
Stirrer bar 
 Still pot
 Distillation path 
Thimble
Solid
Siphon top
Siphon exit
Expansion adapter 
Condenser 
Cooling water in
Cooling water out

4. THE SOXHLET EXTRACTOR Continuous extraction of a component from a solid mixture. Boiling solvent vapors rise up through the larger side-arm

5. Condensed drops of solvent fall into the porous cup, dissolving out the desired component from a solid mixture

6. When the smaller side-arm fills to overflowing, it initiates a siphoning action.

7. Residual solvent then drains out of the porous cup, as fresh solvent drops continue to fall into the porous cup.

8. . . . and the cycle repeats . . .

9. It should look something like THIS:

10. The solvent, containing the dissolved component, is siphoned into the boiler below

11. ROTARY EVAPORATOR