Decomposition of Fluorinated Ionic Liquids to Fluoride Ions Using Superheated Water: An Efficient Approach for Recovering Fluorine from the Waste of Fluorinated Ionic Liquids

Abstract

Fluorinated ionic liquids are cutting-edge materials investigated for electrolytic media for energy-related applications. Although their industrial usages are being spread, waste treatment techniques for these materials are not well established, because they are thermally and chemically stable, owing to the presence of strong carbon-fluorine bonds, and incineration produces hydrogen fluoride gas, which seriously damages incinerators. We describe herein our recent efforts to decompose fluorinated ionic liquids to F− ions (i.e., mineralization) by use of superheated water, with the aim for closing the loops on fluorine element. A methodology that enables complete mineralization of the ionic liquids bearing [(CF3SO2)2N]− anion moiety is demonstrated.

Keywords

• ionic liquid
• superheated water
• fluorine
• mineralization