The CO2 absorption and desorption analysis of tri-solvent MEA + EAE + AMP compared with MEA + BEA + AMP along with “coordination effects” evaluation

The slow kinetics of CO2 absorption and high energy cost of CO2 desorption were the main challenges for CO2 capture technology. To overcome these drawbacks, a novel tri-solvent MEA (monoethanolamine) + EAE (2-(ethylamino)ethanol) + AMP (2-amino-2-methyl-1-propanol) was prepared at different amine concentrations of 0.1 ~ 0.5 + 2 + 2 mol/L. The CO2 absorption and desorption experiments were conducted on MEA + EAE + AMP and their precursor MEA + EAE to evaluate the absorption–desorption parameters. Results demonstrated that the optimized concentrations of the bi-blend were 0.2 + 2 mol/L for absorption and 0.4 + 2 mol/L for desorption. For the tri-solvent, the optimized concentration was 0.2 + 2 + 2 mol/L, consistently for both abs-desorption sides. Compared with tri-solvent of MEA + BEA + AMP, MEA + EAE + AMP proved better in absorption but poorer in desorption, while its CO2 loading of operation line was 0.35 ~ 0.70 mol/mol, higher than that of 0.30–0.60 mol/mol MEA + BEA + AMP. These results led to another tri-solvent candidate of amine solvents in an industrial pilot plant.