Precipitation regime for selected amino acid salts for CO2 capture from flue gases

The tendency of alkaline (sodium, potassium and lithium) salts of taurine, β-alanine, sarcosine and L-proline to form precipitates under varying operational conditions of CO2 absorption has been investigated. CO2 absorption experiments have been performed at 293.15 and 313.15 K, at partial pressures relevant for capturing CO2 from flue gas conditions and amino acid salt concentrations up to the saturation concentration. In addition to this ‘window of operation’ for the (non-) precipitation regime, the identity of precipitates formed was revealed and relevant properties like density of the saturated aqueous amino acid salt solutions at 293.15 K have been determined.