| abstract |
Provided is an ionic liquid, represented by the formula K + A − , having a very low content of impurities, especially a low content of halogen ions and/or a low content of alkali metal, wherein K + is a quaternary ammonium ion, for example an imidazolium ion. Also provided is a quaternarization process for making the ionic liquid in reacted with an acid ester such as a sulfate or phosphate. |