An Amine Double Functionalized Composite Strategy for CO2 Adsorbent Preparation using a ZSM‐5/KIT‐6 Composite as a Support

Abstract An amine double functionalized composite strategy is used to fabricate grafted‐impregnated micro‐/mesoporous composites for CO 2 capture. The micro‐/mesoporous three‐dimensional cross straight zeolite and cubic silica structural ZSM‐5/KIT‐6 composite is used as a support, N 1 ‐(3‐trimethoxysilylpropyl)diethylenetriamine (TMPTA) is used as the grafted component, and tetraethylenepentamine (TEPA) or branched polyethyleneimine (PEI) is used as the impregnated component. The amine efficiency, adsorption kinetics, enthalpy of adsorption, thermal stability, regeneration performance, the effects of types of impregnated amines (TEPA or PEI) and loadings (30–60 %), and temperatures (60–90 °C) on CO 2 adsorption performance are investigated using thermal gravimetric analyzer (TGA) in the mixed gases (15 % CO 2 and the balance is N 2 ). At 75 °C, the double functionalized sample with TEPA impregnation displays the highest CO 2 adsorption capacity of 6.28 mmol g −1 even at high TEPA loading of 60 %, while that of 4.69 mmol g −1 is obtained for the PEI‐impregnated compound at PEI loading of 50 %. The former has higher amine efficiency and faster kinetics as well as higher enthalpy. The composites demonstrate excellent CO 2 adsorption performance compared to other amine double functionalized silicas, indicating the prospect of these adsorbents for CO 2 capture from actual flue gas after desulfurization (60–85 °C).