Soxhlet Extractor Condenser Tubes

The Soxhlet extractor, invented by Franz von Soxhlet in 1879, automates solvent extraction. Solvent boils in a flask below, its vapour rises and is condensed above, and the condensed solvent drips onto the sample held in a thimble; when the chamber fills, a siphon empties it back into the flask, and the cycle repeats — so the sample is repeatedly washed with fresh, clean solvent.

Because each cycle uses freshly distilled solvent, the method extracts efficiently with a modest solvent volume, which is why it remains the reference technique for measuring fat and oil content and extracting residues and analytes from solids.

Fat and oil (total-fat) determination, pesticide and residue extraction, polymer and material extraction, and natural-product isolation, in food and feed analysis, environmental labs and research chemistry.

A borosilicate 3.3 extractor body with a siphon arm and side tube, used with a matching condenser above and a boiling flask below, all joined by standard-taper ground-glass joints (such as 24/40 or 29/32). The sample sits in a thimble inside the body. Components are matched into a working set by joint size.

Assemble with matching ground joints (lightly greased or clipped) and ensure cooling water flows through the condenser before heating, so solvent vapour is fully condensed. Use anti-bumping granules in the flask and heat gently; never run a Soxhlet with flammable solvent near an open flame without proper precautions. Let the apparatus cool before dismantling.

Each component is formed from borosilicate 3.3 with its ground-glass joints, then annealed. The siphon geometry is made to cycle reliably. Joint sizing (so components mate), siphon function and thermal performance are the key checks; sets are matched by joint standard.