2. SOXHLET EXTRACTOR
• A Soxhlet extractor is lab equipment designed for processing certain kinds of
solids.
• These device only required where the desired compound has a limited
Solubility in a Solvent and the impurity is Insoluble in that solvent.
• These device also allow for continuous treatment of a sample with a solvent
over a period of hours or days to extract compounds of interest.
3. INVENTION
• It was invented in 1879 by a scientist named
FRANZ VON SOXHLET.
• It was first invented for the Quantification
of Fat in the Milk.
• Then, it has been frequently used for the
extraction of lipids in agricultural chemistry.
4. SOXHLET EXTRACTOR
• A Soxhlet extractor has three main sections:
1. Percolator (boiler and reflux) which circulates the solvent,
2. Thimble (made of thick filter paper) which retains the solid to be extracted,
3. Siphon mechanism which periodically empties the thimble.
5. COMPONENTS
1. Stirrer bar
2. Still Pot
3. Distillation Path
4. Thimble
5. Solid
6. Siphon top
7. Siphon exit
8. Expansion adapter
9. Condenser
10. Cooling water in
11. Cooling water out
6. PROCEDURE
• Normally a solid material containing some desired compound to be extracted is placed inside the
thimble made from thick filter paper which is loaded to the main chamber of Soxhlet extractor. The
Soxhlet extractor is placed into a flask containing the extraction solvent..
• The solvent is heated to reflux. The solvent vapour travels up a distillation arm. The condenser
ensures that any solvent vapour cools and drips back down into the chamber housing the solid
material.
• Then the chamber slowly fills with warm solvent. Some of the desired compound will then dissolve
in the warm solvent. When the Soxhlet chamber is almost full, the chamber is automatically emptied
by a siphon side arm, with the solvent running back down to the distillation flask.
• After extraction the solvent is removed, by means of a rotary evaporator, yielding the extracted
compound. The non-soluble portion of the extracted solid remains in the thimble and is usually
discarded.
• This cycle may be allowed to repeat many times, over hours or days. During each cycle non-volatile
compound dissolves in the solvent, and desired compound is concentrated in the distillation flask.
7. ADVANTAGES
• It is able to extract solute from insoluble impurities.
• It is mechanically gentle on the samples but still efficient in separation.
• It is often used as a benchmark when developing new extraction methods.
9. APPLICATION
It is the most useful apparatus for Solid-liquid extraction in various fields such
as:
• Pharmaceutics,
• Environment,
• Foodstuffs
10. ESTIMATION OF FAT IN FOOD
• First of all, Dry the product and remove
moisture in order to facilitate entry of the
organic solvent, because moisture restrict the
entry of organic solvent. Then size reduction is
there to increase the surface area and due to it
there is larger exposed surface.
• After this, go for acidic hydrolysis which helps
in breaking of protein fat emulsion and
increase the availability of fat for the solvent.
After that collect the solvent by distillation.
11. CONCLUSION
Extraction is essential for isolation of different chemical constituent from crude drug material.
Extraction depends on properties of material to be extracted. Hence it is necessary to study
extraction methods in detail.