Ammonia modification of activated carbon to enhance carbon dioxide adsorption: Effect of pre-oxidation

▶ Decomposition of oxygen functionalities was an intermediate stage to development of active sites before amination for the formation of nitrogen surface groups. ▶ Oxidation followed by high temperature amination considerably enhanced the CO2 uptake at higher temperatures. ▶ Compared to the textural characteristics, formation of basic nitrogen functionalities plays a more active role on CO2 adsorption at higher temperatures. ▶ CO2 capture capacity depends on both the type and amount of the nitrogen surface groups introduced onto the carbon surface.