A multiphasic liquid is a

mixture In chemistry, a mixture is a material made up of two or more different chemical substances which can be separated by physical method. It is an impure substance made up of 2 or more elements or compounds mechanically mixed together in any proporti ...

consisting of more than two

immiscible Miscibility () is the property of two chemical substance, substances to mix in all mixing ratio, proportions (that is, to fully dissolution (chemistry), dissolve in each other at any concentration), forming a homogeneity and heterogeneity, homoge ...

liquid Liquid is a state of matter with a definite volume but no fixed shape. Liquids adapt to the shape of their container and are nearly incompressible, maintaining their volume even under pressure. The density of a liquid is usually close to th ...

phases. Biphasic mixtures consisting of two immiscible phases are very common and usually consist of an organic

solvent A solvent (from the Latin language, Latin ''wikt:solvo#Latin, solvō'', "loosen, untie, solve") is a substance that dissolves a solute, resulting in a Solution (chemistry), solution. A solvent is usually a liquid but can also be a solid, a gas ...

and an

aqueous An aqueous solution is a solution in which the solvent is water. It is mostly shown in chemical equations by appending (aq) to the relevant chemical formula. For example, a solution of table salt, also known as sodium chloride (NaCl), in wat ...

phase ("oil and water"). Multiphasic liquids can be used for selective

liquid–liquid extraction Liquid–liquid extraction, also known as solvent extraction and partitioning, is a method to separate compounds or metal complexes, based on their relative solubility, solubilities in two different Miscibility, immiscible liquids, usually wate ...

s or for decorative purposes, e.g. in

cosmetics Cosmetics are substances that are intended for application to the body for cleansing, beautifying, promoting attractiveness, or altering appearance. They are mixtures of chemical compounds derived from either Natural product, natural source ...

. While it is possible to get multilayered phases by layering

nonpolar In chemistry, polarity is a separation of electric charge leading to a molecule or its chemical groups having an electric dipole moment, with a negatively charged end and a positively charged end. Polar molecules must contain one or more polar ...

and aqueous phases of decreasing densities on top of each other, these phases will not separate after mixing like true multiphasic liquids.

Compositions

The following types of multiphasic liquids exist:

Triphasic systems

* Nonpolar solvent / aqueous biphasic mixture *: ''e.g. using

hexane Hexane () or ''n''-hexane is an organic compound, a straight-chain alkane with six carbon atoms and the molecular formula C6H14. Hexane is a colorless liquid, odorless when pure, and with a boiling point of approximately . It is widely used as ...

heptane Heptane or ''n''-heptane is the straight-chain alkane with the chemical formula H3C(CH2)5CH3 or C7H16. When used as a test fuel component in anti-knock test engines, a 100% heptane fuel is the zero point of the octane rating scale (the 100 poi ...

cyclohexane Cyclohexane is a cycloalkane with the molecular formula . Cyclohexane is non-polar. Cyclohexane is a colourless, flammable liquid with a distinctive detergent-like odor, reminiscent of cleaning products (in which it is sometimes used). Cyclohexan ...

, or

mineral oil Mineral oil is any of various colorless, odorless, light mixtures of higher alkanes from a mineral source, particularly a distillate of petroleum, as distinct from usually edible vegetable oils. The name 'mineral oil' by itself is imprecise, ...

as the nonpolar solvent'' ** Nonpolar solvent / polar solvent / salt / water **: ''e.g. 100 ml mineral oil, 100 ml

isopropanol Isopropyl alcohol (IUPAC name propan-2-ol and also called isopropanol or 2-propanol) is a colorless, flammable, organic compound with a pungent alcoholic odor. Isopropyl alcohol, an organic polar molecule, is miscible in water, ethanol, an ...

, 75 ml

water Water is an inorganic compound with the chemical formula . It is a transparent, tasteless, odorless, and Color of water, nearly colorless chemical substance. It is the main constituent of Earth's hydrosphere and the fluids of all known liv ...

, 35 g

calcium chloride Calcium chloride is an inorganic compound, a Salt (chemistry), salt with the chemical formula . It is a white crystalline solid at room temperature, and it is highly soluble in water. It can be created by neutralising hydrochloric acid with cal ...

'' ** Nonpolar solvent / water-soluble

polymer A polymer () is a chemical substance, substance or material that consists of very large molecules, or macromolecules, that are constituted by many repeat unit, repeating subunits derived from one or more species of monomers. Due to their br ...

A, water-soluble polymer B, water **: ''e.g. hexane,

polyethylene oxide Polyethylene glycol (PEG; ) is a polyether compound derived from petroleum with many applications, from industrial manufacturing to medicine. PEG is also known as polyethylene oxide (PEO) or polyoxyethylene (POE), depending on its molecular we ...

dextran Dextran is a complex branched glucan (polysaccharide derived from the condensation of glucose), originally derived from wine. IUPAC defines dextrans as "Branched poly-α-d-glucosides of microbial origin having glycosidic bonds predominantly C-1 ...

, water'' ** Nonpolar solvent / water-soluble polymer / salt / water **: ''e.g. hexane, polyethylene oxide,

sodium sulfate Sodium sulfate (also known as sodium sulphate or sulfate of soda) is the inorganic compound with formula Na2SO4 as well as several related hydrates. All forms are white solids that are highly soluble in water. With an annual production of 6 mill ...

, water'' ** Nonpolar solvent A / solvent B / polymer soluble in solvent B and water / water **: ''e.g. heptane, dichloromethane, polyethylene oxide, water'' * Nonpolar solvent A / solvent B / polymer soluble in solvent B and water / salt / water *: ''e.g. 16.3% heptane, 21.7% dichloromethane, 9.5% polyethylene oxide, 51.5% water, 0.1% sodium sulfate'' * Nonpolar solvent /

hydrophobic In chemistry, hydrophobicity is the chemical property of a molecule (called a hydrophobe) that is seemingly repelled from a mass of water. In contrast, hydrophiles are attracted to water. Hydrophobic molecules tend to be nonpolar and, thu ...

salt / water *: ''e.g. iso-octane, Aliquat 336 (methyltrioctylammonium chloride, a phase transfer catalyst), water'

**: ''or: cyclohexane, 1-Butyl-3-methylimidazolium hexafluorophosphate, bmim-PF₆ (an

ionic liquid An ionic liquid (IL) is a salt (chemistry), salt in the liquid state at ambient conditions. In some contexts, the term has been restricted to salts whose melting point is below a specific temperature, such as . While ordinary liquids such as wate ...

), water'

* Hydrophobic

– water – hydrocarbon systems ** e.g. 1-butyl-3-methylimidazolium hexafluorophosphate – water – cyclohexane

Tetraphasic systems

* Nonpolar solvent A / solvent B / polymer soluble in solvent B and water / salt / water *: ''e.g. 10.9% heptane, 15.5% dichloromethane, 7.1% polyethylene oxide, 66.5% sodium sulfate (> 0.1%) in water'' * Nonpolar solvent / Polar solvent / salt / water / Fluorinated solvent **: ''e.g.'' Hexane, isopropanol, brine, perfluoromethylcyclohexane *Non polar solvent / Aprotic polar solvent / Water / Fluorinated solvent **: ''e.g.'' Octane, 5-methyl-1,3-dioxolane-4-one, water, perfluorodecaline

Higher-order multiphasic systems

A system with eight phases is known. In addition to a hydrocarbon and an aqueous phase, it includes a

silicone oil A silicone oil is any liquid polymerized siloxane with organic side chains. The most important member is polydimethylsiloxane. These polymers are of commercial interest because of their relatively high thermal stability and their lubricating prop ...

, an

aniline Aniline (From , meaning ' indigo shrub', and ''-ine'' indicating a derived substance) is an organic compound with the formula . Consisting of a phenyl group () attached to an amino group (), aniline is the simplest aromatic amine. It is an in ...

and a fluorous phase, and molten

phosphorus Phosphorus is a chemical element; it has Chemical symbol, symbol P and atomic number 15. All elemental forms of phosphorus are highly Reactivity (chemistry), reactive and are therefore never found in nature. They can nevertheless be prepared ar ...

gallium Gallium is a chemical element; it has Chemical symbol, symbol Ga and atomic number 31. Discovered by the French chemist Paul-Émile Lecoq de Boisbaudran in 1875, elemental gallium is a soft, silvery metal at standard temperature and pressure. ...

and mercury.

References

{{reflist

External links

Chem. Commun. 1998, 787
''Polymer induced multiphase generation in water/organic solvent mixtures. Strategies towards the design of triphasic and tetraphasic liquid systems'' (pdf)

''Multiphase aqueous cleansing composition'' * ttps://www.youtube.com/watch?v=xcMSHy3CqXA (Movie) Oil and water separation by molecular dynamics simulation Heterogeneous chemical mixtures