The performance and mechanism of CO2 desorption and corrosion in N-methyldiethanolamine aqueous solutions blended with amino acid ionic liquids

The CO2 desorption performance of N-methyldiethanolamine(MDEA)-Tetramethylammonium glycinate ([N1111] [Gly]), MDEA-1-butyl-3-methylimidazolium lysinate ([Bmim][Lys]) aqueous solutions was investigated. The influences of amino acid ionic liquids (AAILs) type and AAILs concentration on CO2 desorption were demon-strated on the basis of experiments. The corrosion characteristics of 20# carbon steel in the MDEA-AAILs-CO2 aqueous solutions were also determined, and the effects of temperature, AAILs concentration, AAILs type, and CO2 loading on the corrosion rate were analyzed. Fourier transform infrared spectroscopy (FT-IR), nuclear magnetic resonance carbon spectroscopy (13C NMR) and scanning electron microscopy (SEM), energy dispersive X-ray spectroscopy (EDS) characterization were used to evaluate the CO2 desorption mechanism and corrosion mechanism, respectively. It is found that AAILs have a good performance in the desorption process and they can effectively reduce the corrosion rate of amine aqueous solution.