Ionic liquids are very popular materials and they enjoy a plethora of applications in various domains of physical sciences.
For example, they are used as “solvents” for organic, organometallic syntheses and catalysis, as electrolytes in electrochemistry, in fuel and solar cells, as lubricants, as a stationary phase for chromatography, as matrices for mass spectrometry, supports for the immobilization of enzymes, in separation technologies, as liquid crystals, templates for the synthesis of mesoporous, nano-materials and ordered films, materials for embalming and tissue preservation, etc.
Here is provided a map of the applications of ionic liquids.
- Homogeneous and heterogeneous catalyst
For some applications, ionic liquids offer the advantage of both homogeneous and heterogeneous catalysts. This is because selected ionic liquids can be immiscible with the reactants and products but dissolve the catalysts.
- “This has the advantages of a solid for immobilizing the catalyst, with the advantages of a liquid for allowing the catalyst to move freely”
- Robert Morland, first major U.S. meeting on ionic liquids, held at the American Chemical Society meeting in San Diego.
The French Petroleum Institute, in Paris, have commercially licensed an ionic liquids-based process that uses these properties for preparing polybutene dimers used in plastics, automobile tires, and related materials.
- Biological reactions media
- “Enzymes are also stable in ionic liquids, opening the possibility for ionic liquids to be used in biological reactions, such as the synthesis of pharmaceuticals”
- James Davis,first major U.S. meeting on ionic liquids
In 2000, chemical ingeneers from the University of Pittsburgh, in Pensylvania, used enzymes in an ionic liquid to synthetize Z-aspartame, a precursor of the artificial sweetener.
Rhodococcus R312, a whole-cell biocatalyst, also works in ionic liquids.
Scientists involved with ionic liquids also belive that they will be used for completely new applications, for example:
- Treatment of high-level nuclear waste
- “Ionizing radiation does not affect ionic liquids, so they could even be used to treat high-level nuclear waste”
- Ken Seddon,first major U.S. meeting on ionic liquids
- Removing of metal ions
In another application, Davis and Rogers have designed and synthetized several new ionic liquids to remove cadmium and mercury from contaminated water. When these water-insoluble ionic liquids come in contact with contaminated water, they snatch the metal ions out of waterand sequester them in the ionic liquid.
- Purification of gases
- “Ionic liquids can selectively dissolve and remove gases and could be used for air purification on submarines and spaceships”
- Davis, first major U.S. meeting on ionic liquids
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