A multiphasic liquid is a mixture consisting of more than two immiscible liquid phases. Biphasic mixtures consisting of two immiscible phases are very common and usually consist of an organic solvent and an aqueous phase ("oil and water").

Multiphasic liquids can be used for selective liquid–liquid extractions or for decorative purposes, e.g. in cosmetics.

While it is possible to get multilayered phases by layering nonpolar 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

  1. e.g. using hexane, heptane, cyclohexane, or mineral oil as the nonpolar solvent

  Nonpolar solvent / polar solvent / salt / water

  1. e.g. 100ml mineral oil, 100ml isopropanol, 75ml water, 35g calcium chloride

  Nonpolar solvent / water-soluble polymer A, water-soluble polymer B, water

  1. e.g. hexane, polyethylene oxide, dextran, water

  Nonpolar solvent / water-soluble polymer / salt / water

  1. e.g. hexane, polyethylene oxide, sodium sulfate, water

  Nonpolar solvent A / solvent B / polymer soluble in solvent B and water / water

  1. e.g. heptane, dichloromethane, polyethylene oxide, water

  Nonpolar solvent A / solvent B / polymer soluble in solvent B and water / salt / water

  1. e.g. 16.3% heptane, 21.7% dichloromethane, 9.5% polyethylene oxide, 51.5% water, 0.1% sodium sulfate

  Nonpolar solvent / hydrophobic salt / water

  1. e.g. iso-octane, Aliquat 336 (methyltrioctylammonium chloride, a phase transfer catalyst), water https://web.archive.org/web/20070103190343/http://venus.unive.it/alvise/index_file/page0003.htm

  2. or: cyclohexane, bmim-PF6 (an ionic liquid), water http://www.mariecurie.org/annals/volume3/berthod.pdf

Hydrophobic ionic liquid – 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

  1. 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

1. e.g. Hexane, isopropanol, brine, perfluoromethylcyclohexane

Non polar solvent / Aprotic polar solvent / Water / Fluorinated solvent

1. 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, an aniline and a fluorous phase, and molten phosphorus, gallium and mercury.

See also

• Separating funnel

References

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)

• US patent application 20050215443 Multiphase aqueous cleansing composition

• (Movie) Oil and water separation by molecular dynamics simulation