Capture of CO2 by highly concentrated alkanolamine solutions in a rotating packed bed

Abstract The capture of CO 2 in a rotating packed bed (RPB) using highly concentrated alkanolamine solutions has been proved to be an effective way to enhance the absorption efficiency of CO 2 . In this investigation, the effects of alkanolamine concentration on the CO 2 removal efficiency and mass transfer coefficients ( K G a ) at various lean CO 2 loadings were studied. Monoethanolamine and 2‐methyl‐amino‐ethanol solutions were used to absorb CO 2 in an RPB. Experimental results showed that increasing the alkanolamine concentration effectively enhanced the CO 2 absorption efficiency of a fresh absorbent. For an absorbent with a high CO 2 loading, an optimal alkanolamine concentration was observed because the viscosity of the absorbent dramatically increased at high alkanolamine concentration and high CO 2 loading. A correlation of K G a was proposed and the mass transfer coefficient can be expressed as a function of the free alkanolamine concentration and the viscosity of the absorbent.