Performance of a hybrid solvent of amino acid and ionic liquid for CO₂ capture

Advanced solvents are under development to reduce the energy consumption for CO₂ capture from the coal-fired power plant. In this work, an amino acid, sodium glycinate (SG), and an ionic liquid, [Bmim][BF₄], were blended to be used as solvent for CO₂ capture. The parametric tests such as blending mole ratio, temperature, CO₂ partial pressure and oxygen concentration were investigated. Results revealed the highest CO₂ absorption rate was achieved when the blending mole ratio of SG and [Bmim][BF₄] was 4:1. Compared with the pure SG solution, the CO₂ absorption rate into those blends was 40% higher than that into the pure SG solution under the same tested conditions. The high temperature and CO₂ partial pressure facilitated the CO₂ absorption. Overall, the blends of SG and [Bmim][BF₄] possessing a high CO₂ absorption rate, good anti-oxidation ability, and good regeneration efficiency may be an alternative of the MEA solution for CO₂ capture.