Evaluating CO₂ Capture Performance of Trisolvent MEA-BEA-AMP with Heterogeneous Catalysts in a Novel Bench-Scale...

To reduce the huge energy cost of CO₂ capture technology applicable in industry, the CO₂ absorption-desorption performance was conducted in a novel bench-scale pilot plant with hot water as a heat source. The trisolvent MEA(monoethanol amine)-BEA(butylethanol amine)-AMP(2-amino-2-methyl-1-propanol) was prepared at a specific concentration to analyze the CO₂ capture performance and compared with 5 M MEA as the benchmark. Meanwhile, several solid acid catalysts, blended H-ZSM-5/γ-Al₂O₃(1/2), or HND-8, were packed in the desorber, and the solid base catalyst, CaCO₃ or CaMg(CO₃)₂, was packed in the absorber with random packing. The CO₂ absorption efficiency (AE), cyclic capacity (CC), and heat duty (HD) were tested onto MEA-BEA-AMP and MEA under various operating conditions. Experimental results indicated that the performance of 4.3 mol/L MEA-BEA-AMP was significantly better than 5 M MEA under both catalytic and noncatalytic operation. The most energy efficient combination of this study was discovered as 0.3 + 2 + 2 mol/L MEA-BEA-AMP, with 50 g (CaCO₃/CaMg(CO₃)₂) in the absorber and 150 g H-ZSM-5/γ-Al₂O₃(1/2) in the desorber. The heat duty reached as low as 2.4 GJ/tCO₂ at a F_G of 7.0 L/min and a F_L of 70 mL/min. These results were highly applicable in an industrial amine scrubbing pilot plant for CO₂ capture.