Improving CO2 adsorption with new amine-functionalized Y-type zeolite

In this work, a new synthesized Y-type zeolite with an Si/Al molar ratio of 2.5 (NaY) was modified with amines, in order to probe the influence of the modification of the adsorbent’s surface on CO2 adsorption. The three selected amines were diethanolamine, tetraethylenepentamine, and 2- methylaminoethanol. The surface nature of NaY was changed after amine modification, which causes a significant increase in the CO2 adsorption capacity. The CO2 adsorption capacity of the aminemodified NaY increased with temperature. The mechanism of CO2 adsorption on NaY is usually a physical interaction, but it seems that after amine modification, chemical mechanism is the dominant mechanism for the chemical interaction between CO2 and amine groups. The adsorbents were characterized by surface area and porosity analysis, X-ray diffraction, Fourier transform infrared spectroscopy, thermal gravimetric analysis, and scanning electron microscopy. The CO2 adsorption capacity was measured by the volumetric method at 298 and 348 K. The CO2 adsorption capacity of TEPA-NaY, DEA-NaY, and 2-MAE-NaY at 298 K was 60.63. The CO2 adsorption capacity of TEPANaY, DEA-NaY, and 2-MAE-NaY at 348 K were 92.9, 78, and 85.42, respectively. These results showed that amine-functionalized NaY zeolites have excellent adsorption potential for CO2 adsorption at high temperatures.

Keywords:

CO2 Adsorption , Y-Type Zeolite , amine modification , chemisorption , physisorption