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Accumulation of greenhouse gases (GHGs) in the atmosphere is responsible for enhanced global warming of our planet. In the present study, hollow silica spherical particles (HSSP) and multi-walled carbon nanotubes containing amine groups composite (denoted NH2-CNT@HSSP) were synthesized as adsorbents in a single-step and used to investigate the adsorption capacity and selectivity of CO2, CH4 and N-2. The crystal structures and morphology of HSSP modified with different amounts of NH2 -CNTs were characterized by X-ray diffraction (XRD), Fourier transform infrared (FT-IR), Scanning electron microscopy (SEM), Transmission electron microscopy (TEM), thermogravimetric analysis (TGA) and N-2 adsorption/desorption isotherms. The CO2 adsorption capacity of the NH2 -CNT5/FISSP is better than HSSP. CO2 adsorption capacity for HSSP is about 7.71 mmol g(-1) when HSSP were composited with the amine-modified carbon nanotubes, CO2 adsorption capacity is increased (from 7.71 to 13.80 mmol g(-1)) at 298 K and 20 bar. CO2 capture on the adsorption sites by amine loading is believed to occur via chemisorption mechanism by formation of ammonium carbamate. The optimum adsorbent showed its stability with the adsorption capacity remaining constant over three adsorption/desorption cycles. (C) 2019 Published by Elsevier Ltd.