Zeolite Y supported CuCl (CuCl/Y) has been prepared with CuCl 2 as precursor by a monolayer dispersion method, followed by activation with CO. The samples are investigated for CO adsorption and characterized by inductively coupled plasma optical emission spectrometry, X-ray diffraction, N 2 adsorption/desorption and X-ray photoelectron spectroscopy. The characterization results reveal that CuCl 2 supported on zeolite Y can be completely reduced to CuCl after activation at 663 K in CO, and the monolayer dispersion capacity of CuCl on zeolite Y support is 5 mmol/g zeolite Y. The resulting adsorbent displays high CO adsorption capacity, high CO/N 2 , CO/CH 4 and CO/CO 2 adsorption selectivities, and excellent reversibility and regenerability. The adsorption equilibrium isotherms of CO on the adsorbents at temperatures up to 333 K can be well fitted by both the Langmuir and Sips models, and the integral thermodynamic data of Gibbs’ energy change (Δ G ), entropy change (Δ S ) and enthalpy change (Δ H ) are calculated from the fitted Langmuir adsorption equations. The negative Δ G and Δ H values indicate that the adsorption process of CO on CuCl/Y adsorbent is spontaneous and exothermic. The negative Δ S value indicates that the adsorbed CO molecules on the adsorbent are in an ordered arrangement. [ABSTRACT FROM AUTHOR]