Dynamic performance of CO2 adsorption with tetraethylenepentamine-loaded KIT-6

A promising adsorbent for CO2 removal from flue gas was prepared by introducing tetraethylenepentamine (TEPA) into KIT-6 type mesoporous silica using post-synthetic impregnation. The as-prepared adsorbents were characterized by X-ray powder diffraction (XRD), thermal gravimetric analysis (TGA), nitrogen adsorption/desorption as well as adsorption-column-breakthrough measurements. Surface area, pore size and pore volume of TEPA-loaded KIT-6 adsorbent decrease with the increasing of TEPA loading, while its fundamental pore structure is unchanged. The dynamic adsorption capacity increases from 1.5 mmol/g-adsorbent to 2.9 mmol/g-adsorbent when the amount of loaded TEPA increases from 10 wt.% to 50 wt.% at 333 K. The net adsorption capacity is about 72% of dynamic adsorption capacity. Regarding the regeneration performance of CO2 adsorbent, the suitable desorption temperature is nearly 373 K. The dynamic adsorption capacity drops slightly (about 5%) during forty cycles of adsorption/desorption. The adsorbent of KIT-6 modified by TEPA exhibits excellent CO2 adsorption/desorption performance.