Synthesis and characterization of new absorbents for CO2 capture

Abstract

In the present paper we investigated seven synthetic and eleven commercial amine based absorbents with systematic modification of their chemical structures. A 30wt% of these aqueous amine solutions were used for performance evaluation. Three laboratory experiments, which were gas scrubbing test, reaction calorimetry and vapor-liquid equilibrium measurement, were conducted in order to obtain fundamental information on their absorption rate, saturated CO2 loading, absorption capacity, heat of reaction and cyclic capacity. The results of these absorbents were then compared with conventional absorbents MEA and MDEA which were chosen as the base case for all comparisons. We found four high performance absorbents with advantages of high absorption rate, high cyclic capacity and low heats of reaction compared with MEA and MDEA. It is expected that the use of lower reaction enthalpy and higher absorption rate can reduce absorbent regeneration energy costs significantly. The results presented in this paper can provide basic guidelines for finding potential secondary and tertiary amine based absorbents that may lead to a better approach for the development of new absorbent systems in the CO2 capture area.