Imidazolium‐Based Poly(ionic liquid)s as New Alternatives for CO₂ Capture

Abstract

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 CO2 capture and compared with classical ionic liquids with similar counter anions. In addition to poly(ionic liquid)s with often-applied ions such as BF4 (-) , PF6 (-) , NTf2 (-) , trifluoromethanesulfonate (OTf(-) ) and Br(-) , for the first time [BIEMA][acetate] was synthesised, which revealed a remarkably high CO2 sorption performance that exceeded the poly(ionic liquid)s studied previously on average by a factor of four (12.46 mg gPIL (-1) ). This study provides an understanding of the factors that affect CO2 sorption and a comparison of the CO2 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 CO2 sorption.

Investigation of gas permeation properties of film forming polymeric ionic liquids (PILs) based on polybenzimidazoles

“…PILs and ILs based on Ac -as anion are known to possess exceptionally high CO 2 sorption and selectivity (esp. S CO 2 =S N 2 ) over other gases [20,42,43]. In present series as well, [TMPBI-BuI][Ac] exhibited highest CO 2 sorption (Fig.…”

Polymeric ionic liquids for CO2 capture and separation: potential, progress and challenges

“…PIL-7e containing acetate as counter ion synthesized for the first time gave CO 2 sorption four-fold higher (12.46 mg/g PIL ) relative to 2.88, 2.99, 3.31, 2.05 and 1.53 mg/g PIL for PIL-7a-d,f respectively (Table 1). 51 Bulky structures of TFMS and NTf 2 anions reduced the free volume hindering CO 2 penetration towards the cation, which is mainly responsible for sorption. 40,42 Exchange of Br in place of NTf 2 can reduce the volume of microvoids in PIL by 37 %.…”

“…51 In this connection, PIL-7a with Br anion and PIL-7b with BF 4 anion having different molecular weights were compared. CO 2 uptake of Br containing PIL-7a was amplified with increase in the molecular weight.…”

“…These results proved that CO 2 sorption is not much dependent on particle size. 51 The presence of moisture can also cause problems in processing and practical applications and even in trace amounts; it may considerably alter the functionality of PILs. So, the moisture is considered to decrease CO 2 sorption performance of PILs.…”

Polysulfone-ionic liquid based membranes for CO2/N2 separation with tunable porous surface features

“…A more advanced approach is the synthesis of specifically designed "polymerisable ionic liquids" (PILs) or PIL-IL solid-liquid composites. This method requires more sophisticated organic synthesis and polymerisation techniques [4][5][6][7][8][9][10][11][12].…”