Schematic of a simple distillation setup.
Distillation equipment used by the 3rd century alchemist Zosimos of Panopolis, from the Byzantine Greek manuscript Parisinus graces.
Hieronymus Brunschwig's Liber de arte Distillandi de Compositis (Strassburg, 1512) Science History Institute
A retort
Old Ukrainian vodka still
Simple liqueur distillation in East Timor
A batch still showing the separation of A and B.
Dimethyl sulfoxide usually boils at 189°C. Under a vacuum, it distills off into the receiver at only 70°C.
Perkin triangle distillation setup
 | Stirrer bar/anti-bumping granules
 | Still pot
 | Fractionating column
 | Thermometer/Boiling point temperature
 | Teflon tap 1
 | Cold finger
 | Cooling water out
 | Cooling water in
 | Teflon tap 2
 | Vacuum/gas inlet
 | Teflon tap 3
 | Still receiver
Short path vacuum distillation apparatus with vertical condenser (cold finger), to minimize the distillation path;
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 | Still pot with stirrer bar/anti-bumping granules
 | Cold finger – bent to direct condensate
 | Cooling water out
 | cooling water in
 | Vacuum/gas inlet
 | Distillate flask/distillate.
Typical industrial distillation towers
Diagram of a typical industrial distillation tower
Section of an industrial distillation tower showing detail of trays with bubble caps
Large-scale, industrial vacuum distillation column

Process of separating the components or substances from a liquid mixture by using selective boiling and condensation.

- Distillation

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Separation process

Method that converts a mixture or solution of chemical substances into two or more distinct product mixtures.

An ore extraction process broken into its constituent unit operations (Quincy Mine, Hancock, MI ca. 1900)

In the case of oil refining, crude is subjected to a long series of individual distillation steps, each of which produces a different product or intermediate.


Reverse of vaporization.

Condensation forming in the low pressure zone above the wing of an aircraft due to adiabatic expansion
Condensation on a window on a cold day.
Condensation on the outside of a window, due to it being in front of the sea which regularly produces moist sea spray.
In cloud chambers a liquid (sometimes water, but usually isopropanol) condenses upon contact with a particle of radiation thus producing an effect similar to contrails
Condensation on a window during a rain shower.

Condensation is a crucial component of distillation, an important laboratory and industrial chemistry application.

Volatility (chemistry)

Material quality which describes how readily a substance vaporizes.

Bromine liquid readily transitions to vapor at room temperature, indicating a high volatility.
A log-lin vapor pressure chart for various liquids
Normal boiling point (red) and melting point (blue) of linear alkanes vs. number of carbon atoms.
A crude oil distillation column.

When the vapors are collected, this process is known as distillation.


Process that takes away mineral components from saline water.

Schematic of a multistage flash desalinator A – steam in   B – seawater in     C – potable water out D – brine out (waste)     E – condensate out     F – heat exchange    G – condensation collection (desalinated water) H – brine heater 
The pressure vessel acts as a countercurrent heat exchanger. A vacuum pump lowers the pressure in the vessel to facilitate the evaporation of the heated sea water (brine) which enters the vessel from the right side (darker shades indicate lower temperature). The steam condenses on the pipes on top of the vessel in which the fresh sea water moves from the left to the right.
Plan of a typical reverse osmosis desalination plant
The Shevchenko BN-350, a former nuclear-heated desalination unit in Kazakhstan
Scheme of the desalination machine: the desalination box of volume V_box contains a gel of volume V_gel which is separated by a sieve from the outer solution volume V_out =V_box- V_gel. The box is connected to two big tanks with high and low salinity by two taps which can be opened and closed as desired. The chain of buckets expresses the fresh water consumption followed by refilling the low-salinity reservoir by salt water.
Mangrove leaf with salt crystals

Desalination processes are usually driven by either thermal (in the case of distillation) or mechanical (e.g. in the case of reverse osmosis) energy types.

Fractional distillation

Separation of a mixture into its component parts, or fractions.

Fractional distillation
Typical industrial fractional distillation columns
Diagram of a typical industrial distillation tower
Crude oil is separated into fractions by fractional distillation. The fractions at the top of the fractionating column have lower boiling points than the fractions at the bottom. All of the fractions are processed further in other refining units.
Chemical engineering schematic of typical bubble-cap trays in a distillation tower

It uses distillation to fractionate.

Oil refinery

Industrial process plant where petroleum is transformed and refined into useful products such as gasoline (petrol), diesel fuel, asphalt base, fuel oils, heating oil, kerosene, liquefied petroleum gas and petroleum naphtha.

Anacortes Refinery (Marathon), on the north end of March Point southeast of Anacortes, Washington, United States
A petrochemical refinery in Grangemouth, Scotland
ExxonMobil oil refinery in Baton Rouge, Louisiana (the fourth-largest in the United States)
Refinery, Bayport Industrial Complex, Harris County, Texas
Neste Oil refinery in Porvoo, Finland
The oil refinery in Haifa, Israel, is capable of processing about 9 million tons (66 million barrels) of crude oil a year. Its two cooling towers are landmarks of the city's skyline.
Crude oil is separated into fractions by fractional distillation. The fractions at the top of the fractionating column have lower boiling points than the fractions at the bottom. The heavy bottom fractions are often cracked into lighter, more useful products. All of the fractions are processed further in other refining units.
A breakdown of the products made from a typical barrel of US oil
Storage tanks and towers at Shell Puget Sound Refinery (Shell Oil Company), Anacortes, Washington
Schematic flow diagram of a typical crude oil distillation unit as used in petroleum crude oil refineries
Fire-extinguishing operations after the Texas City Refinery explosion
Refinery of Slovnaft in Bratislava
Oil refinery in Iran
Sample of crude oil (petroleum)
Cylinders of liquified petroleum gas
Sample of gasoline
Sample of kerosene
Sample of diesel fuel
motor oil
Pile of asphalt-covered aggregate for formation into asphalt concrete

Oil refineries are typically large, sprawling industrial complexes with extensive piping running throughout, carrying streams of fluids between large chemical processing units, such as distillation columns.


Any material that can be made to react with other substances so that it releases energy as thermal energy or to be used for work.

Wood was one of the first fuels used by humans.
Wood as fuel for combustion
Coal is a solid fuel
A gasoline station
Fuel gauge for gasoline on a 50 ccm scooter, with the typical pictogram of a gas pump
A 20-pound (9.1 kg) propane cylinder
Extraction of petroleum
Two CANDU ("CANada Deuterium Uranium") fuel bundles, each about 50cm long and 10cm in diameter
Nuclear fuel pellets are used to release nuclear energy.

Crude oil was distilled by Persian chemists, with clear descriptions given in Arabic handbooks such as those of Muhammad ibn Zakarīya Rāzi.


A copper retort
A glass retort
Retort in use

In a chemistry laboratory, a retort is a device used for distillation or dry distillation of substances.

Dry distillation

Heating of solid materials to produce gaseous products .

Glowing-hot metal bar due to incandescence

If there are no chemical changes, just phase changes, it resembles classical distillation, although it will generally need higher temperatures.

Distilled water

Water that has been boiled into vapor and condensed back into liquid in a separate container.

Bottle for distilled water in the Real Farmacia in Madrid
A boiling water distiller. Boiling tank on top and holding tank on the bottom.
Typical laboratory distillation unit

One method of removing impurities from water and other fluids is distillation.