Different Approaches for the Development of Low-Cost CO2 Adsorbents

摘要

Different carbon materials were tested as precursors for the production of CO2\udadsorbents. The chemical modification of the surface of the prepared adsorbents was\udstudied by means of three different approaches: impregnation with amines, electrophilic\udaromatic substitution and heat treatment in the presence of ammonia. The samples were\udchemically characterized and the porous texture was evaluated from the N2 adsorption\udisotherms at -196 ºC. The CO2 adsorption capacities of the adsorbents at 25 and 100 ºC\udwere evaluated in a thermogravimetric analyzer. In general, the incorporation of basic\udnitrogen functionalities enhanced the CO2 capture capacities of the modified carbons\udbut this increase depended on the textural properties of the support and the surface modification methodology. CO2 adsorption capacities of up to 111 mg CO2/ g at room\udtemperature were attained. All the tested samples were completely regenerated when\udsubjected to heat treatment at 100 ºC under inert atmosphere.