Microfluidic Studies of CO₂ Sequestration by Frustrated Lewis Pairs

Frustrated Lewis pairs (FLPs) comprising sterically hindered Lewis acids and bases offer the capability to reversibly capture CO₂ under mild reaction conditions. The determination of equilibrium constants and thermodynamic properties of these reactions should enable assessment of the efficiency of a particular FLP system for CO₂ sequestration and provide insights for design of new, efficient formulations of FLP catalysts for CO₂ capture. We have developed a microfluidic approach to studies of FLP–CO₂ reactions, which provides their thermodynamic characterization that is not accessible otherwise. The approach enables the determination of the equilibrium reaction constants at different temperatures, the enthalpy, the entropy, and the Gibbs energy of these reactions, as well as the enhancement factor. The microfluidic methodology has been validated by applying it to the well-characterized reaction of CO₂ with a secondary amine. The microfluidic approach can be applied for fundamental thermodynamic studies of other gas–liquid reactions