Summary: | The Paris Agreement and one of its goals, “carbon neutrality,” require intensive studies on CO<sub>2</sub> absorption and desorption processes. When searching for ways of reducing the huge energy cost of CO<sub>2</sub> desorption in the amine scrubbing process, the combination of blended amine with solid acid catalysts turned out to be a powerful solution in need of further investigation. In this study, the tri-solvent MEA (monoethanolamine) + EAE(2-(ethylamino)ethanol) + AMP(2-amino-2-methyl-1-propanol) was prepared at: 0.2 + 2 + 2, 0.5 + 2 + 2, 0.3 + 1.5 + 2.5 and 0.2 + 1 + 3 mol/L. The heterogeneous catalytic CO<sub>2</sub> desorptions were tested with five commercial catalysts: blended γ-Al<sub>2</sub>O<sub>3</sub>/H-ZSM-5, H-beta, H-mordenite, HND-8 and HND-580. Desorption experiments were conducted via a recirculation process with direct heating at 363 K or using temperature programming method having a range of 303–363 K. Then, the average CO<sub>2</sub> desorption rate, heat duty and desorption factors were studied. After comparison, the order of CO<sub>2</sub> desorption performance was found to be HND-8 > HND-580 > H-mordenite > Hβ > blended γ-Al<sub>2</sub>O<sub>3</sub>/H-ZSM-5 > no catalyst. Among the other combinations, the 0.2 + 1 + 3 mol/L MEA + EAE + AMP with HND-8 had a minimized heat duty (HD) of 589.3 kJ/mol CO<sub>2</sub> and the biggest desorption factor (DF) of 0.0277 × (10<sup>−3</sup> mol CO<sub>2</sub>)<sup>3</sup>/L<sup>2</sup> kJ min. This study provided a kind of tri-solvent with catalysts as an energy-efficient solution for CO<sub>2</sub> absorption and desorption in industrial CO<sub>2</sub> capture pilot plants.
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