We have investigated the effect of ball-milling over calcined Mg-Al hydrotalcite, with regard to its CO₂ adsorption capacity. The prepared materials were systematically characterized by X-ray diffraction, scanning electron microscopy and N₂ physisorption measurements. The results reveal an excellent adsorption capacity of CO₂ by calcined Mg-Al hydrotalcite; however, when this adsorbent was treated by ball-milling for 2 h, a slight decrease in its CO₂ adsorption capacity was observed, mainly attributable to the decreased surface area, total pore volume, pore size and the formation of particle aggregates of the aforementioned hydrotalcite. Therefore, alterations in structure, texture and morphology of calcined Mg-Al hydrotalcite during the ball-milling treatment do not optimize its CO₂ adsorption capacity.

Keywords: CO₂ adsorption, Calcined Mg-Al hydrotalcite, Co-precipitation synthesis, Ball-milling effect.