Ionic Liquids Impregnated ZIFS for Selective Gas Storage and Separation A Multi Scale Modelling Approach

Abstract

The capture and storage of CO2 from different flue gas streams is really important to reduce the carbon footprint. Here, an effort was made to understand the structure, stability, and CO2 capture and storage ability of different IL-based membranes. For supporting the ILs, ZIFs such as ZIF-8 and ZIF-3 were selected from a series of ZIFs. The ILs are well confined at the nanopores of the ZIFs and the resulting composites shows good structural stability due to the strong interactions at solid and liquid interface. [BMIM]+ cation and series of anions were selected for the impregnation into the ZIFs. From the DFT studies, it is interesting to note that the nitrogenous anionic ILs are not stable at the ZIF-8 surface, whereas the non-nitrogenous anions are stable at the interface and shows good CO2 adsorption both at the interface and in the pure state. Also, it was found that similar hydrophobicity of the framework and IL (like-like pair) can enhance the CO2 adsorption newline