page_title: Steam distillation
section_title: Equipment
hierarchical_section_title: Steam distillation / Equipment
caption_attribution_description: English: Hydrodistillation using the Clevenger-type apparatus. (A) Power regulator; (B) Heating mantle with round bottom flask containing water and aromatic leaves; (C) Clevenger-type apparatus which returns the hydrosol to the still and maintains the essential oil phase, but only for essential oils that are less dense than water and therefore float; (D) The condenser.
context_page_description: Steam distillation is a separation process which consists in distilling water together with other volatile and non-volatile components. The steam from the boiling water carries the vapor of the volatiles to a condenser, where both are cooled and return to the liquid or solid state; while the non-volatile residues remain behind in the boiling container.
  If the volatiles are liquids not miscible with water, they will spontaneously form a distinct phase after condensation, allowing them to be separated by decantation or with a separatory funnel. In that case, a Clevenger apparatus may be used to return the condensed water to the boiling flask, while the distillation is in progress. Alternatively, the condensed mixture can be processed with fractional distillation or some other separation technique.
  Steam distillation can be used when the boiling point of the substance to be extracted is higher than that of water, and the starting material cannot be heated to that temperature because of decomposition or other unwanted reactions. It may also be useful when the amount of the desired substance is small compared to that of the non-volatile residues.
context_section_description: On a lab scale, steam distillations are carried out using steam generated outside the system and piped through macerated biomass or steam generated in-situ using a Clevenger-type apparatus.
caption: Hydrodistillation using the Steam distillation apparatus, Clevenger-type apparatus. (A) Power regulator; (B) Heating mantle with round bottom flask containing water and aromatic leaves; (C) Clevenger-type apparatus which returns the hydrosol to the still and maintains the essential oil phase, but only for essential oils that are less dense than water and therefore float; (D) The condenser.[6]
exif: {}