Adsorption of CO2 on Amine-Functionalized Y-Type Zeolites

Abstract

Commercially available Y-type zeolite with a Si/Al molar ratio of 60 (abbreviated as Y60) was modified by tetraethylenepentamine (TEPA) to study their characterizations and adsorption/desorption properties of CO2 from gas streams. The surface nature of Y60 was changed after TEPA modification, which causes a significant enhancement in CO2 adsorption capacity. The CO2 adsorption capacity of Y60(TEPA) increased with the temperature at 30−60 °C but decreased with the temperature at 60−70 °C. The mechanism of CO2 adsorption on Y60 is entirely a physical interaction but becomes mainly attributable to a chemical interaction after TEPA modification. The CO2 adsorption capacity of Y60(TEPA) was influenced by the presence of water vapor and reached as high as 4.27 mmol of CO2/g of sorbent at a water vapor of 7%. The cyclic CO2 adsorption showed that the adsorbed CO2 could be desorbed from the surface of Y60(TEPA) at 75 °C for 4 h. The adsorption capacities and the physicochemical properties of Y60(TEPA) were preser...