Evaluating CO₂ desorption performance in CO₂-loaded MEA solution with bifunctional catalysts

In this work, four bifunctional Al₂O₃/HZSM-5 catalysts (Al-ZSM) were prepared and characterized with various techniques. The regeneration behaviors of a 5 M monoethanolamine (MEA) solvent with four Al-ZSM catalysts were studied at an initial CO₂ loading of 0.5 mol CO₂/mol amine and the temperature of 96 °C. The results reveal that all the catalysts improve the CO₂ desorption performance, the Al-ZSM catalysts show higher catalytic performance than the virginal catalysts, and the Al-ZSM can decrease the regeneration energy requirement by 23.3-34.2% as compared with the catalyst-free test. The prominent activities of Al-ZSM can be attributed to their improved Brϕnsted acid sites (BAS), mesopore surface area (MSA) and basic sites, which resulted from the good synergistic reaction between the Al₂O₃ and HZSM-5. From the results of this study, the Al-ZSM catalysts demonstrate superior catalytic performances for the rich MEA solvent regeneration process, and show an excellent stability, explicitly have the potential to be a promising industrial catalyst for CO₂ capture.