Tetraethylenepentamine-Modified Activated Semicoke for CO2 Capture from Flue Gas

Abstract

To separate CO2 from coal-fired power plant emissions, semicoke, which is cheap and easy to obtain, was further activated to use as the carrier and tetraethylenepentamine (TEPA) was impregnated in the activated semicoke to prepare solid amine sorbents. The effects of activating agents, adsorption temperature, and the presence of water on CO2 sorption were investigated in a fixed-bed reactor, and the regenerability and adsorption kinetics for prepared sorbents were also studied. The equilibrium adsorption capacity for N2-activated semicoke (SE-N2) was 2.70 and 2.14 mmol/g at 20 °C when water was absent and present, respectively, and the equilibrium adsorption capacity for 10 wt % TEPA-modified N2-activated semicoke (SE-N2-TEPA10%) was 3.24 and 3.58 mmol/g at 60 °C when water was absent and present, respectively. After 10 cyclic regenerations, the adsorption capacity for SE-N2-TEPA10% reduced by 7.7% under dry conditions, and SE-N2-TEPA10% showed good regenerability.