Developing Imidazole-Based Solvents for CO2 Capture Using Economic and Scalable Precursors

Developing low impact, low cost, and application specific technologies for carbon capture (CC) will rectify the economics of modern energy production with growing environmental concerns. While developments in ionic liquid (IL) capture technology have shown promise for greenhouse gas (GHG) reduction, the possibility of new ILs with more desirable properties must be investigated. With lower viscosity and lower vapor pressure and equivalent carbon capture capacity to current ILs, imidazole-based solvents have the potential to better address carbon capture on this scale. Furthermore, laboratory synthesis of alkylimidazoles has been accomplished using only readily available chemical precursors, effectively lowering the cost of production, and thus incentivizing the wide scale adoption of carbon capture technology.  Using imidazolate salts, in our synthesis sodium imidazolate (NaIm), several 1-n-alkylimidazoles were synthesized based on a recently published method along with several other functionalized imidazoles (2-ethyl-1-n-alkylimidazoles, 1-n-cycloalkylimidazoles, 4-methyl-1-n-alkylimidazoles etc.), for a current total 46 solvents synthesized.  Imidazole-based solvents were characterized experimentally by measuring density, viscosity, and CO₂ solubility.