Using titanium-containing blast furnace slag produced during the smelting process of vanadium titanium magnetite concentrate as raw material, porous zeolite molecular sieve adsorbent was synthesized by the step of "acid treatment-alkali melting-hydrothermal crystallization". The effect of sodium metaaluminate addition on the structure type of porous zeolite was investigated. Dynamic adsorption method was used to evaluate the CO₂ adsorption performance of the as-synthesized samples under different conditions, and the adsorption behavior was analyzed by data fitting with different kinetic models. The results of XRD、SEM、FTIR characterizations showed that the hydrothermal crystallization product in turn completed the transformation from “amorphous-preliminary crystallization-FAU type-LTA type” zeolite molecular sieve structure with the increase of sodium metaaluminate addition. The results of CO₂ adsorption experiments showed that the Z-4 sample activated at 350 °C exhibited excellent adsorption performance at adsorption temperature of 25 °C, with the CO₂ breakthrough and saturation adsorption capacities reaching 2.16 mmol?g_-1 ^{and 3.39 mmol?g}_-1^, respectively. The CO₂ adsorption behavior conformed to the pseudo-second-order kinetic model, and the adsorption was mainly physical and chemical adsorption, and the adsorption rate could reach 4.709 mmol?g_-1^?s_-1. After 5 regeneration cycles, the saturation adsorption capacity remained basically unchanged, showing a good cyclic stability.