Synthesis and selection of hindered new amine absorbents for CO2 capture

This work focuses on synthesizing and selecting hindered new amine absorbents to reduce the regeneration energy cost for CO2 capture. To achieve this target we synthesized seven secondary and two tertiary amine based CO2 absorbents with systematic modification of their chemical structures by an appropriate placement of substituent functional groups especially the alkyl functions (e.g. methyl, isopropyl, isobutyl, secondary butyl etc.), relative to the position of the amino group. Performances evaluations of these new absorbents in aqueous solutions were carried out based on their CO2 absorption rate, absorption capacity and heat of reaction measurements. Particular attention was paid to absorbents with a potential for high absorption rate and low heats of reaction. The results for the synthesized amino alcohols were then compared with conventional absorbents AMP and MDEA which were chosen as the base case for all comparisons. We found three high performance absorbents with advantages of high absorption rate and low heats of reaction compared with AMP and MDEA. Absorbents higher CO2 absorption rate and lower heat energy consumption characteristics will reduce the regeneration energy cost of CO2 during stripping.