Summary: | New amines for reactive absorption of CO2 from synthesis gas were developed, synthesized, and characterized. All studied amines are derivatives of triacetone amine (TAA) and differ only in the substituent of the basic TAA ring structure. In a first step, a short list of candidates was established. Selected candidates were then synthesized and studied experimentally. Gas solubility, rate of absorption, liquid-liquid and solid-liquid equilibrium, viscosity, and chemical equilibria were studied. Based on the knowledge gained in the evaluation of the results, new candidates were proposed. In the iterative process, about 50 amines were considered and 27 of them were actually synthesized and investigated. All synthesized amines were assessed on the same data basis. From the 27 synthesized amines the eight most promising for industrial applications were evaluated with the newly developed NoVa short-cut method. This method yields estimates for the energy demand. The well-established solvent MDEA/PZ (Piperazin-activated Methyldiethanolamine) was included in the study. Four candidates show an improved performance compared to MDEA/PZ, with energy savings up to 30 %. The large body of results was also used to establish relationships between the chemical structure of the amines and their properties as reactive solvents for CO2 capture. NMR data on the chemical reactions in the studied systems and data from titration curves was used for that purpose. The influence of differences in the chemical structure of the amines on the different properties was elucidated and related to the performance of the solvents for CO2 capture.
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