Introduction of Potassium Iodide as an Inhibitor for Oxidative Degradation of Amines

Oxidative degradation of amines for CO2 capture is a challenge that has yet to be overcome. This work presents the potential of using potassium iodide as a stable inhibitor, potentially without the need for replenishment in the capture process. The experimental results prove that the addition of only 1wt% potassium iodide to a 30 wt% ethanolamine (aq.) solution significantly reduces amine loss at absorber conditions, even if the amine solution already is degraded. 3-Aminopropanol seems to be equally stabilized under oxidative conditions as ethanolamine. Thermal stability and corrosivity as well as viscosity, density and vapour liquid equilibrium properties seem unaltered by the addition of a small amount of salt. The results presented here show why potassium iodide should further be evaluated as an inhibitor for oxidative degradation of amines.