Ionic Liquids

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Introduction
Ionic liquids is a broaden term covering several possible systems. Ionic liquids are liquids that consist of exclusively ions, which exhibit ionic conductivity. The traditional definition known is molten salts or fused salt, which tend to have high melting points. For a while now the generalized definition of ionic liquids has only limited itself to the specific definition, which have melting points or has glass transition temperatures of 100 degrees. There are also the room temperature ionic liquids. Although liquids like ethyl ammonium nitrate is considered to fall under the definition, but aqueous solutions are not classified as ionic liquids. Also Binary mixtures that are liquid and consist of entirely of ions can be considered ionic liquids. There are also room temperatures ionic liquids. As you can see the progression of science broadens the definition of classification. Ionic Liquids can greatly contribute to the development of green chemistry, like replacing toxic flammable volatile organic solvents, reducing or preventing chemical wastage and pollution, and improving the safety of chemical process and products.
Characteristics of Ionic Liquids
Ionic liquids has opened up new types of studies because at one point in time ionic liquids were at the bottom of the bucket for research, but now it has an unlimited amount of theoretical studies. In theoretical thoughts, many ionic liquid creations are possible. There are almost a limitless number of ionic liquids systems, which in theory, is by mixing two or more simple ionic liquids. When comparing organic solvents, ionic liquids have insignificant vapor pressures, which basically means they do not evaporate under normal circumstances. Unlike most organic mole...

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... distillation as they have insignificant vapor pressure.
There are multiple systems to use to lower the halide content in an ionic liquid. Which include the usage of silver nitrate to precipitate the silver halide, also ion chromatography is another commonly used purification method.
The impurity can be minimized by extracting an ionic liquid into an organic solvent and washing with small amounts of deionized water. Which is removed in a rotary evaporator. The liquid is later dried with a heating vacuum. This does not work with all types of ionic liquids.
Since ionic liquids do not crystallize when cooled, they can not be purified by the crystallization. They tend to have yellow to brown coloration caused because of the contaminations. Stirring the liquid in liquid activated by charcoal and then passing it through a column of alumina usually remove the color.

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