distillation
- Domaine
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- chimie chimie analytique
- Date
Définitions :
Action de purifier un corps par passage de l'état liquide à l'état gazeux, par chauffage puis retour à l'état liquide par condensation. Transfert d'un liquide d'un point à un autre avec passage intermédiaire par l'état de vapeur.
Procédé de séparation thermique de constituants dans le cas de mélanges liquides, dans lequel les éléments constitutifs à séparer sont vaporisés puis récupérés par condensation sous forme liquide.
Notes :
Le chauffage peut être solidaire, d'où le « distillateur solaire ».
Le phénomène de distillation est à l'origine de la présence dans la fumée de nombreux constituants de tabac.
Terme :
- distillation n. f.
Traductions
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anglais
Date :Définition
A thermal process for the de-fractionizing of liquid mixtures, in which the parts to be separated are evaporated and the various fractions are then condensed into liquid form.
A process of evaporation and recondensation whereby liquids are separated into various fractions according to their boiling points or boiling ranges.
Separation of the components of a mixture (usually of liquids or solutions) by heating to the boiling point and condensing the resulting vapor.Note :
In multi-component mixtures such as petroleum, the various fractions have different boiling points; thus it is possible to effect separation by condensing the vapor of each component in turn, the lower-boiling fractions distilling off first (fractional distillation). Distillation of petroleum thus yields naphthas, gasoline, kerosine, fuel oils, and ultimately a tarry or waxy residue, depending on the geographical origin of the petroleum. Distillation is also used to purify products such as alcohol. In nature, simple evaporation from the ocean surface provides pure water vapor, which later condenses as rain (distilled water). Destructive distillation (a form of pyrolysis) is performed on solid materials such as coal and wood by heating them out of contact with air to obtain coal tar, coke, charcoal, etc. Flash distillation is an efficient method of desalting sea water; it involves extremely rapid evaporation and cooling in a multistage unit in which the heat removed in the condensation stage preheats the incoming sea water, similar to the action of a countercurrent heat exchanger.
Terme :
- distillation