Development of N-Functionalized Imidazoles for Industrial Gas Capture

The efficient capture of CO2 from industrial power generation sources is a major challenge. Current studies are investigating the adsorption of CO2 into ionic liquids (ILs). Imidazolium-based ILs have received a great deal of attention for CO2 capture due to their unique physical properties.  However, it has recently been reported that imidazoles – neutral counterparts to imidazolium-based ILs – can offer enhancements in viscosity, cost, and CO2 capacity.  However, the lack of thermophysical property data for neutral imidazole substitutions and chemical permutations makes it difficult to identify and develop future candidates for specific gas processing applications without having to obtain extensive experimental datasets. Using ab initio and molecular mechanics methods, we elucidate thermodynamic and structural properties of a variety of N-functionalized imidazole compounds. Ab initio calculations are used to determine parameters (such as partial charges) for the all-atom Optimized Potentials for Liquid Simulations (OPLS-AA) force field, followed by simulations using the molecular dynamics package Gromacs. We make comparisons with our experimentally-synthesized compounds, providing guidance towards new synthesis targets.