Liebig cooler

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Liebig cooler

The Liebig cooler is a laboratory cooler that condenses vapors and passes them on in a tube. The inventor of the Liebig cooler is not - as the name suggests - Justus Liebig ; the cooler was used before Liebig. However, Liebig made it popular.

Structure and functionality

The Liebig cooler is a tube that is open at both ends and is surrounded by a larger tube. Cooling water flows between the inner and outer tubes, steam or distillate flows in the inner tube . Since the water has a lower temperature than the distillate, it cools it down so that it condenses on the wall of the inner pipe. Steam / distillate and cooling water flow in opposite directions. According to the counterflow principle , the cooling effect is greater than with the same direction of flow. See also: countercurrent distillation and countercurrent condenser

The apparatus is slightly inclined to the horizontal position during operation: The distillate flows downwards in the inner tube following the force of gravity and is collected at the end of the cooler.


Liebig coolers are mainly used in the laboratory for the distillation of liquids, also in high vacuum . For the distillation of liquids with low boiling points, such as diethyl ether , the Liebig cooler is not well suited due to its very small cooling surface: Intensive coolers are then used.

Web links

Commons : Liebig Condenser  - collection of images, videos and audio files

Individual evidence

  1. G. Kahlbaum: The so-called Liebig'sche refrigerator . In: Reports of the German Chemical Society 1896 , 29 , 69–71.