(6dm) Incorporation of Metal Oxides to Activated Carbon for the Adsorption of Acid Gases

Among the greenhouse gases CO₂ contributes more than 60% to global warming because of its huge emission amount. These acid gas is usually present in many natural and anthropogenic processes like the production of biogas, and since CO₂ is abundant in the biogas, their removal is also required to raise the adiabatic flame temperature and minimize corrosion effects over pipelines and other metal accessories. Their elimination is not very easy; however there are some alternatives for carrying out the removal of these components from the gas mixture. Among these, solid adsorption processes are suggested and studied to overcome those inherent problems in chemical absorption. Incorporation of amines has been proposed to enhance the originally limited adsorption capacity and to promote the mass transfer rate of the gases into porous, or mesoporous adsorbents. An attractive option to eliminate acid gases which may be less expensive is the use of modified activated carbon. The incorporation of metal oxides like CaO, MgO and ZnO to activated carbon could improve the basic character of the carbon, leading to solids with better properties for the adsorption of acid gases like CO₂. Therefore in this study a new method for the incorporation in-situ of metal oxides to carbon is proposed. The adsorption capacity of these solids was studied through CO₂ adsorpion analyzed by FT-IR, the material were also characterized by XRD, physisorption of N₂, electronic microscopy, size particle determination and thermal gravimetric analysis (TGA).