Oxidative degradation of 1-amino-2-propanol for CO2 capture and its inhibition via amine blending

Amine blend is a viable method to formulate superior absorbents for CO 2 capture from flue gas. However, the understanding of the degradation of blended amines, especially the interaction effect on the degradation pathway is limited, which restricts the solvent development. In this work, the oxidative degradation of 1-amino-2-propanol (1AP) and its blends with various tertiary amines is studied by analyzing amine loss, alkalinity loss, viscosity change, NH 3 emission, and heat-stable salt generation. Experimental results show that both triethanolamine and N -methyldiethanolamine have an excellent inhibition effect on 1AP oxidative degradation, reducing 1AP loss from 47.0% to 6.5% and 8.5%, respectively. The reaction pathways for the oxidative degradation of single and blended 1AP solutions are proposed and evaluated by density functional theory calculations. Computational results show that the reactions between 1AP peroxide radicals and peroxide radicals of tertiary amines reduce 1AP loss, which agrees with experimental results.