Research Progress of CO2 Capture and Separation by Functionalized Ionic Liquids and Materials

CO2 emission is a serious global problem. CO2 capture technology is indispensable to achieve the strategic goals of carbon peaking and carbon neutrality in China. Ionic liquids as new media have attracted much attention in the field of CO2 capture and separation due to their unique advantages of low volatility, good gas solubility and structure designability. This review focuses on research progresses of amino and non-amino functionalized ionic liquids, ionic liquid hybrid solvents, ionic liquid modified adsorbents and membranes for CO2 capture and separation reported in the past five years. The influence of amino groups and electronegative functional sites on CO2 separation performance and mechanism, and the role of functionalized ionic liquids in hybrid solvents, adsorbents and membranes were summarized. Finally, the future development direction and prospect of ionic liquid-based CO2 capture technologies were also proposed.