Ionic Liquid Catalyzed Amine Solvent for Greatly Improved CO2 Capture Performance

Amine-based solvent absorption technology is the workhorse of large-scale CO2 capture for its reliability and technology maturity. The amine absorption process requires tall absorption columns and high solvent regeneration temperatures (120-140°C), resulting in high capital cost and high energy requirement (typically >2.5 GJ/tonne of CO2). Susteon, in partnership with University of Wyoming, is commercializing homogeneous ionic liquid catalysts which dramatically increases CO2 adsorption and desorption rates in amine solvent.These catalysts can be added to state-of-the-art (SOTA) aqueous amine solvents, non-aqueous amine solvents, and water-lean solvents to effectively transform them into super-efficient CO2 capture solvents that can reduce the absorber tower height and reduce solvent regeneration temperature. Furthermore, when global use of these solvents for CO2 capture becomes widespread, large amount of solvent will be used in all regions of the world. Emissions of the solvent itself and its degradation products could pose problems to the global land, air and water environment. These catalysts, when successfully deployed, will help reduce emissions of amine and its degradation products and prevent the reduction of CO2 emissions at the expense of increasing other emissions and corresponding environmental impact. The other major advantages of the homogeneous catalysts are that they can be added to solvents used in already constructed plants to effectively improve CO2 capture process efficiency, reduce energy consumption and solvent losses. Thus, the use of these catalysts could impact the CO2 capture process by transforming and advancing conventional technologies to much high efficiencies and at lower costs for widespread global adoption.We have performed laboratory and small pilot scale testing for post-combustion capture of CO2 from coal and NGCC flue gases. Large pilot testing is planned for early 2022 for post-combustion. High pressure, pre-combustion CO2 capture testing is also planned for early 2022. These tests are aimed at further verification of the effectiveness of the catalysts. Laboratory data for absorption of 10% CO2 simulated flue gas in 20 wt% monoethanolamine (MEA) solution with and without catalyst are shown in Figure 1.