For the decanting of wine, see
Decanter.
Decantation is a process for the separation of mixtures, carefully pouring a solution from a container in order to leave the precipitate (sediments) in the bottom of the original container. Usually a small amount of solution must be left in the container, and care must be taken to prevent a small amount of precipitate from flowing with the solution out of the container. It is generally used to separate a liquid from an insoluble solid (e.g. in red wine, where the wine is decanted from the potassium bitartrate crystals). Another example is when separating the oil from water after getting them as a mixed liquid out of olives in order to extract olive oil. A mixture of kerosene and water can be separated through decantation.
In other words we can say that decantation is a process by which a liquid layer can be separated from the sediment. Separation of liquid from any other immiscible liquid can also be done by decantation.
A centrifuge may be useful in successfully decanting a solution. The centrifuge causes the precipitate to be forced to the bottom of the container; if the force is high enough, the precipitate may form a hard single solid. Then the liquid can be more easily poured away, as the precipitate will likely remain in its compressed form.
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