N¹-(3-trimethoxysilylpropyl)diethylenetriamine grafted ordered mesoporous silica KIT-6 for CO₂adsorption

Abstract

Abstract. Pure KIT-6 was synthesized by using tri-block copolymer P123 as the structure directing agent and tetraethyl orthosilicate (TEOS) as the silica source. It was functionalized with N 1 -(3-trimethoxysilylpropyl)diethylenetriamine (denoted as 3N) by grafting in solvent at 80 °C. The materials were characterized by X-ray powder diffraction (XRD) and nitrogen adsorption/desorption and thermal gravimetric analysis (TGA). The CO 2 adsorption capacity was studied in a gravimetric analyzer. The resulted showed that the pore structure of KIT-6 was well kept after grafting of amine groups while surface area, pore size and pore volume were decreased. The CO 2 adsorption capacities of 3N-KIT-6 increased first and then decreased with the increase of 3N loading. The maximum adsorption capacity is 3.017mmol/g.