Oil bath

An oil bath is a type of heated bath used in a laboratory. These baths are commonly used to heat reaction mixtures. An oil bath is essentially a container of oil that is heated by a hot plate. Generally, silicone oil is used in modern oil baths, although mineral oil, cottonseed oil and even phosphoric acid have been used in the past.

Another use of an oil bath is to filter particulates out of air, by leading the air stream through an (unheated) oil bath. This type of air filter was used in car engines, but has been replaced by modern paper air filters.

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