Imidazolium‐Based Poly(ionic liquid)s as New Alternatives for CO 2 Capture

Solid imidazolium‐based poly(ionic liquid)s with variable molecular weights that contain the poly[2‐(1‐butylimidazolium‐3‐yl)ethyl methacrylate] (BIEMA) cation and different counter anions were evaluated in terms of CO 2 capture and compared with classical ionic liquids with similar counter anions. In addition to poly(ionic liquid)s with often‐applied ions such as BF 4 − , PF 6 − , NTf 2 − , trifluoromethanesulfonate (OTf − ) and Br − , for the first time [BIEMA][acetate] was synthesised, which revealed a remarkably high CO 2 sorption performance that exceeded the poly(ionic liquid)s studied previously on average by a factor of four (12.46 mg g PIL −1 ). This study provides an understanding of the factors that affect CO 2 sorption and a comparison of the CO 2 capture efficiency with the frequently used sorbents. Moreover, all the studied sorbents were reusable if regenerated under carefully selected conditions and can be considered as suitable candidates for CO 2 sorption.