A New Approach to CO2 Capture and Conversion Using Imidazolium Based-Ionic Liquids as Sorbent and Catalyst

Although the carbon capture and storage (CCS) technologies are receiving great attention for mitigation of greenhouse gas effect, the increasing costs and energy penalties associated to its implementation are still major drawbacks. However, the use of CO₂ as a C1 building block in organic synthesis can be very attractive for the design of environmentally friendly processes. In this work, we have studied both the CO₂ sorption and catalytic activities of some imidazolium based ionic liquids (ILs) for cyclic carbonate synthesis. The work demonstrates that the presence of a nucleophilic group in the catalytic system can enhance its performance by the use of an IL with a halide anion or by mixing a halide co-catalyst with ILs. The latter approach allowed to obtain an effective system for CO₂ capture constituted by a fluorinated IL plus ZnBr₂ that performs cyclic carbonate synthesis with 90% yield and 82% of selectivity.

ionic liquids; CO₂ capture; cyclic carbonate