A BST R ACT The thermodynamics of carbon dioxide adsorption in the protonic zeolite H-McM-22 (Si:Al-16:1) was investigated by means of adsorption calorimetry and variable-temperature IR spectioscopy. a technique that affords determination of standard adsorption enthalpy (AM) and (AS) from of entropy analysis a series of IR spectra recorded over a temperature range while simultaneously equilibrium measuring pressure inside a closed IR cell. AH° resulted to be -24.5 (*2)kl mol-1. while for the entropy change the value of Aso --115 (110) mol-1 K-1 was obtained. The obtained AHo value is compared with those reported in the literature for the adsorption of co2 on other zeolites, and discussed in the context of carbon dioxide capture and sequestration. 2014 Elsevier BV. All rights reserved.