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Study of physisorbed and chemisorbed carbon dioxide (CO 2 ) species was carried out on the NaX zeolite modified by cationic exchanges with bivalent cations (Ca 2+ and Ba 2+ ) by temperature-programmed desorption of CO 2 (CO 2 -TPD). Others results were obtained by infrared to complete the study. The results of this research showed, in the physisorption region (213 -473 K), that the cationic exchanges on NaX zeolite with bivalent cations increase slightly the interactions of CO 2 molecule with adsorbents and/or cationic site. Indeed, the desorption energies of physisorbed CO 2 obtained on the reference zeolite NaX (13.5 kJ•mol −1 ) are lower than that of exchanged zeolites E-CaX and E-BaX (15.77 and 15.17 kJ•mol −1 respectively). In the chemisorbed CO 2 region (573 -873 K), the desorption energies related to desorbed species (bidentate carbonates: 2 3 CO − ) on the exchanged zeolites E-CaX and E-BaX are about 81 kJ•mol −1 , higher than the desorbed species (bicarbonates: 3 HCO − ) on the reference R-NaX (62 kJ•mol −1 ). In addition, the exchanged E-BaX zeolite develops the secondary adsorption sites corresponding to bicarbonates species with desorption energies of 35 kJ•mol −1 lower to desorption energies of bicarbonates noted on the reference zeolite NaX.