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The objective of this research was to investigate CO2 adsorption capacity of tetraethylenepentamine-functionalized basic-modified calcined hydrotalcite (TEPA/ b-cHT) sorbents at atmospheric pressure formed under varying TEPA loading levels,temperatures,sorbent weight to total gaseous flow rate (W/F) ratios and CO2 concentrations in the influent gas.The TEPA/b-cHT sorbents were characterized bymeans of X-ray diffraction (XRD),Fourier transform infrared spectrometry (FT-IR),thermal gravimetric analysis (TGA),Brunauer-Emmet-Teller (BET) analysis of nitrogen (N2) adsorption/desorption and carbon-hydrogen-nitrogen (CHN) elemental analysis.Moreover,a full 24 factorial design with three central points at a 95％ confidence interval was used to screen important factor(s) on the CO2 adsorption capacity.It revealed that 85.0％ variation in the capacity came from the influence of four main factors and the 15.0％ one was from their interactions.A face-centered central composite design response surface method (FCCCD-RSM) was then employed to optimize the condition,the maximal capacity of 5.5-6.1 mmol/g was achieved when operating with a TEPA loading level of 39％-49％ (W/W),temperature of 76-90℃,W/F ratio of 1.7-2.60 (g·sec)/cm3 and CO2 concentration of 27％-41％ (V/V).The model fitted sufficiently the experimental data with an error range of ± 1.5％.From cyclical adsorption/desorption and selectivity at the optimal condition,the 40％TEPA/b-cHT still expressed its effective performance after eight cycles.