Amine neutralized amino acid as CO2 absorbents: A quantitative 13C-NMR study

Generally, addition of amine to an aqueous amino acid solution increases the amino acid solubility. In this work solid precipitation was only observed at higher CO2 loadings for l-alanine blended with both MEA and AMP. NMR spectroscopy analysis showed that the precipitate consists mainly of amino acid and bicarbonate/carbonate with very small amounts of amine.