Pure KIT-6 was synthesized using pluronic P123 (PEO20PPO70PEO20, mw similar to 5800 Da) surfactant in mild acidic condition. It was functionalized with (3-aminopropyl) triethoxysilane (APTES) by grafting in dry and aqueous solvent at 80 degrees C. Cubic (Ia3d) structure and uniformity of the adsorbents were analyzed by small angle powder X-ray diffraction (XRD) and high-resolution transmission electron microscopy (HRTEM). Physical properties of the adsorbents were characterized by nitrogen adsorption/desorption behavior, infrared spectroscopy (IR) and thermo gravimetric (TG) analysis. CO2 adsorption/desorption behavior of the adsorbents was studied in a gravimetric analyzer. Optimum amine loading was substantially increased from 1.74 mmol N g(-1) in dry grafting to 2.75 mmol N g(-1) in aqueous grafting. The adsorption capacity was also remarkably increased from 0.90 mmol CO2 g(-1) (An_K_9.0A) to 1.56 mmol CO2 g(-1) (Aq_K_0.20W_9.0A) at 30 degrees C. The heat of adsorption of the process was in the range of 20-32 kJ mol(-1). The adsorbent showed its stability with the adsorption capacity remaining constant over 10 adsorption/desorption cycles. (C) 2014 Elsevier B.V. All rights reserved.