Enhancing regeneration energy efficiency of CO2-rich amine solution with a novel tri-composite catalyst

Abstract

The aqueous amine-based method stands out as the most practical and feasible industrial approach for CO2 removal from flue gases. However, the main barrier arises in the form of the energy demands during the solvent regeneration stage of the process. Multiple Lewis acid sites (LASs) and Bronsted acid sites (BASs) on the surface of nanocomposite of MoO3/Zif-67 (MZ) synergistically boost catalytic activity. Molybdenum oxide is naturally abundant with both types of acid sites (LASs and BASs). Further treatment with phosphotungstic acid (HPW) regulates active acid sites and enriches the catalysts with three distinguishing types of active sites. The novel catalyst named MZC-HPW-20 showed improved CO2 desorption performance, boasting a remarkable 123 % higher CO2 desorption rate and a notable 52 % increase in the amount of desorbed CO2 when compared to the non-catalytic process. While showed a 32 % decrease in energy consumption for regeneration. The nanohybrids incorporating the novel catalyst played a pivotal role in accelerating the breakdown of carbamate, with active sites on their surface facilitating efficient proton transfer. This innovative approach introduces a fresh perspective to amine-based CO2 capture, positioning it as a forefront solution among advanced industrial techniques for the capture of anthropogenic and native CO2 among the available separation technologies.

Keywords

• CO2 desorption
• Amine solvent
• Nanocomposite
• Catalytic regeneration