CO2 Capture by Ionic Liquids - An Answer to Anthropogenic CO2 Emissions?

Ionic liquids (ILs) are efficient solvents for the selective removal of CO2 from flue gas. Conventional, off-the-shelf ILs are limited in use to physisorption, which restricts their absorption capacity. After adding a chemical functionality like amines or alcohols, absorption of CO2 occurs mainly by chemisorption. This greatly enhances CO2 absorption and makes ILs suitable for potential industrial applications. By carefully choosing the anion and the cation of the IL, equimolar absorption of CO2 is possible. This paper reviews the current state of the art of CO2 capture by ILs and presents the current research in this field performed at the Chem Tech Institute of the Ecole d'Ingenieurs et d'Architectes de Fribourg.