Ionic liquids: designer sorbents for CO2 capture

The search for economical and environment-friendly facets is the major driving force for developing efficient technological solutions for capturing atmospheric CO2 in large-scale industrial application. Ionic liquids (ILs) have surfaced as promising designer solvents which are extensively explored in their potential toward CO2 capture and utilization. The present chapter provides a comprehensive overview of the different ILs used in CO2 capture. Moreover, the ability to design unique ILs by altering the cationic and anionic moieties as well as their effects on CO2 capturing potential of ILs is discussed in detail. The effect of functionalization with CO2-philic groups in the cationic/anionic moieties constituting the ILs is further discussed to understand the effect on solubility as well as selectivity of CO2 in ILs. Recent advances in task-specific ionic liquids, functionalized ILs, and mixtures of ILs with water and other organic solvents are highlighted to understand the idea of CO2 capture in these neoteric solvents. At the end, we have discussed the challenges that are restricting the use of IL-based novel technologies in CO2 capture.