Development of novel hybrid ionic fluids for efficient CO2 capture and cellulose dissolution

Abstract

Ionic liquids (ILs) and deep eutectic solvents (DESs) are considered as green solvents and have shown tremendous potential in numerous applications. Despite many advantages, the scientific community across the globe is well aware about some of their limitations. Herein we attempt to develop a novel Hybrid Ionic Fluid (HIF) by combining IL and DES having a common ion that might overcome the individual limitations and show efficient applications. We have developed two HIFs namely Glyn-ChLac and Glyn-EmimCl by combining glyceline (Glyn) DES with choline lactate (ChLac) IL and 1-ethyl-3-methylimidazolium chloride (EmimCl) IL, respectively. Both the HIFs were analyzed by using 1H NMR, DSC, and FTIR techniques and compared them with their respective constituents. Glyn-ChLac HIF shows two- fold CO2 capture compared to its starting material constituents. The desorption experiment and free volume calculation confirm that CO2 capture using HIF is physical adsorption. Similarly, Glyn-EmimCl HIF demonstrates efficient cellulose dissolution when compared with its starting materials. In a time-span of merely 6 seconds, HIF could be able to dissolve 5 wt% of microcrystalline cellulose. Moreover, the solid EmimCl have successfully been used in microwave technique for cellulose dissolution in the form of HIF. The common ion present in both the HIFs could be playing a major role in binding the starting material constituents and eventually leading to efficient applications. Furthermore, the HIFs have more flexibility in tuning the potential by altering the ions as compared to ILs and DES and need more investigation to prove itself as a better alternative green solvent.