Cu-based adsorbents for CO adsorption were efficiently prepared by impregnation activated carbon (AC) with aqueous solution of copper (II) chloride and copper (II) carboxylate. The effects of preparation condition on CO adsorption capacity of the adsorbents were investigated. Characterization of the adsorbents by XRD and N-2 adsorption at 77K showed that cupric salts were completely converted to highly dispersed CuCl on activated carbon after pre-activation, resulting in the stoichiometric adsorption by the coordination of CO with Cu(I). The resulting adsorbents displayed high adsorption selectivity and good adsorption-desorption reversibility for CO with the small adsorption heat, and exhibited broad prospects for the selective separation of CO from mixture gas containing CO2, CH4 and N-2 by pressure swing adsorption. (C) 2010 Elsevier B.V. All rights reserved.