A multiphasic liquid is a mixture

Mixture

In chemistry, a mixture is a material system made up by two or more different substances which are mixed together but are not combined chemically...

 consisting of more than two immiscible

Miscibility

Miscibility is the property of liquids to mix in all proportions, forming a homogeneous solution. In principle, the term applies also to other phases , but the main focus is usually on the solubility of one liquid in another...

 liquid

Liquid

Liquid is one of the three classical states of matter . Like a gas, a liquid is able to flow and take the shape of a container. Some liquids resist compression, while others can be compressed. Unlike a gas, a liquid does not disperse to fill every space of a container, and maintains a fairly...

  phases

Phase (matter)

In the physical sciences, a phase is a region of space , throughout which all physical properties of a material are essentially uniform. Examples of physical properties include density, index of refraction, and chemical composition...

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

Organic compound

An organic compound is any member of a large class of gaseous, liquid, or solid chemical compounds whose molecules contain carbon. For historical reasons discussed below, a few types of carbon-containing compounds such as carbides, carbonates, simple oxides of carbon, and cyanides, as well as the...

 solvent

Solvent

A solvent is a liquid, solid, or gas that dissolves another solid, liquid, or gaseous solute, resulting in a solution that is soluble in a certain volume of solvent at a specified temperature...

 and an aqueous phase ("oil and water"). Multiphasic liquids are rare and only triphasic (three phases) and tetraphasic (four phases) are known.

Multiphasic liquids can be used for selective liquid-liquid extraction

Liquid-liquid extraction

Liquid–liquid extraction, also known as solvent extraction and partitioning, is a method to separate compounds based on their relative solubilities in two different immiscible liquids, usually water and an organic solvent. It is an extraction of a substance from one liquid phase into another liquid...

s or for decorative purposes, e.g. in cosmetics

Cosmetics

Cosmetics are substances used to enhance the appearance or odor of the human body. Cosmetics include skin-care creams, lotions, powders, perfumes, lipsticks, fingernail and toe nail polish, eye and facial makeup, towelettes, permanent waves, colored contact lenses, hair colors, hair sprays and...

.

While it is possible to get multilayered phases by layering nonpolar and aqueous phases of decreasing densities

Density

The mass density or density of a material is defined as its mass per unit volume. The symbol most often used for density is ρ . In some cases , density is also defined as its weight per unit volume; although, this quantity is more properly called specific weight...

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

Triphasic systems

• Nonpolar solvent / aqueous biphasic mixture

  e.g. using hexane

  Hexane

  Hexane is a hydrocarbon with the chemical formula C6H14; that is, an alkane with six carbon atoms.The term may refer to any of four other structural isomers with that formula, or to a mixture of them. In the IUPAC nomenclature, however, hexane is the unbranched isomer ; the other four structures...

  
  , heptane

  Heptane

  n-Heptane is the straight-chain alkane with the chemical formula H3C5CH3 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...

  
  , cyclohexane

  Cyclohexane

  Cyclohexane is a cycloalkane with the molecular formula C6H12. Cyclohexane is used as a nonpolar solvent for the chemical industry, and also as a raw material for the industrial production of adipic acid and caprolactam, both of which being intermediates used in the production of nylon...

  
  , or mineral oil

  Mineral oil

  A mineral oil is any of various colorless, odorless, light mixtures of alkanes in the C15 to C40 range from a non-vegetable source, particularly a distillate of petroleum....

  
   as the nonpolar solvent

  • Nonpolar solvent / polar solvent / salt / water

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

    Calcium chloride

    Calcium chloride, CaCl2, is a salt of calcium and chlorine. It behaves as a typical ionic halide, and is solid at room temperature. Common applications include brine for refrigeration plants, ice and dust control on roads, and desiccation...

    
    

  • Nonpolar solvent / water-soluble polymer
    Polymer
    A polymer is a large molecule composed of repeating structural units. These subunits are typically connected by covalent chemical bonds...
    
     A, water-soluble polymer B, water

    e.g. hexane, polyethylene oxide, dextran

    Dextran

    Dextran is a complex, branched glucan composed of chains of varying lengths...

    
    , water

  • Nonpolar solvent / water-soluble polymer / salt / water

    e.g. hexane, polyethylene oxide, sodium sulfate

    Sodium sulfate

    Sodium sulfate is the sodium salt of sulfuric acid. When anhydrous, it is a white crystalline solid of formula Na2SO4 known as the mineral thenardite; the decahydrate Na2SO4·10H2O has been known as Glauber's salt or, historically, sal mirabilis since the 17th century. Another solid is the...

    
    , water

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

    e.g. heptane, dichloromethane

    Dichloromethane

    Dichloromethane is an organic compound with the formula CH2Cl2. This colorless, volatile liquid with a moderately sweet aroma is widely used as a solvent. Although it is not miscible with water, it is miscible with many organic solvents...

    
    , 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
  Hydrophobe
  In chemistry, hydrophobicity is the physical property of a molecule that is repelled from a mass of water....
  
   salt / water

  e.g. iso-octane

  2,2,4-Trimethylpentane

  2,2,4-Trimethylpentane, also known as isooctane, iso-octane, is an organic compound with the formula 3CCH2CH2. It is one of several isomers of octane . This particular isomer is the standard for 100 point on the octane rating scale...

  
  , Aliquat 336

  Aliquat 336

  Aliquat 336 is a mixture of C8 and C10 chains with C8 predominating. It is a quaternary ammonium salt used as a phase transfer catalyst and metal extraction reagent.-Applications:...

  
   (methyltrioctylammonium chloride, a phase transfer catalyst

  Phase transfer catalyst

  In chemistry, a phase transfer catalyst or PTC is a catalyst that facilitates the migration of a reactant from one phase into another phase where reaction occurs. Phase transfer catalysis is a special form of heterogeneous catalysis. Ionic reactants are often soluble in an aqueous phase but...

  
  ), water http://venus.unive.it/alvise/index_file/page0003.htm

  • or: cyclohexane, bmim-PF₆

    1-Butyl-3-methylimidazolium hexafluorophosphate

    1-Butyl-3-methylimidazolium hexafluorophosphate, also known as BMIM-PF6, is a viscous, colourless, hydrophobic and non-water soluble ionic liquid. Together with 1-butyl-3-methylimidazolium tetrafluoroborate, BMIM-BF4, it is one of the most widely studied ionic liquids and is commercially available...

    
     (an ionic liquid

    Ionic liquid

    An ionic liquid is a salt in the liquid state. In some contexts, the term has been restricted to salts whose melting point is below some arbitrary temperature, such as . While ordinary liquids such as water and gasoline are predominantly made of electrically neutral molecules, ILs are largely made...

    
    ), water http://www.mariecurie.org/annals/volume3/berthod.pdf

• Hydrophobic ionic liquid
  Ionic liquid
  An ionic liquid is a salt in the liquid state. In some contexts, the term has been restricted to salts whose melting point is below some arbitrary temperature, such as . While ordinary liquids such as water and gasoline are predominantly made of electrically neutral molecules, ILs are largely made...
  
  - 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

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.

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