Abstract The most promising technology for carbon dioxide capture from coal and natural gas fired power plants at large scale applications is based on post-combustion method using gas–liquid absorption. The paper evaluates carbon dioxide absorption, at low partial pressures, from flue gases by post-combustion capture using aqueous solutions of various alkanolamines: monoethanolamine (MEA), diethanolamine (DEA), methyldiethanolamine (MDEA), 2-amino-2methyl-1-propanol (AMP) and their corresponding mixtures. At a constant capture rate of about 90%, the performance of these aqueous alkanolamine solutions is compared in terms of solvent loading and overall energy consumption. The objective of the present paper is to assess using a multicriterial analysis (e.g. energy consumption, environmental and operational criteria) the carbon dioxide capture using the above alkanolamines and to investigate the effect of using alkanolamine mixtures as solvent on the gas treatment process. The evaluation was based on Aspen Plus ® simulations. As illustrative example, the case of an IGCC coal-fired power plant generating 375–450 MW e net electricity with and without post-combustion capture was presented in details.