Variable temperature IR spectroscopy (VTIR) was used to investigate the adsorption thermodynamics of carbon monoxide, dinitrogen and carbon dioxide on the protonic zeolite H-Beta. Interaction of the adsorbed gases with the zeolite Bronsted acid sites was found to involve an enthalpy change of -27, -19 and -33 kJ mol(-1) for CO, N-2 and CO2, respectively; the corresponding entropy change was -150, -140 and -146J mol(-1) K-1. The adsorbed gases showed also a weak interaction with silanols, which involves a Delta H-0 value in the approximate range of -7 to -10 kJ mol(-1). These results were discussed in the context of gas separation and carbon capture and sequestration (CCS) using zeolites. (C) 2011 Elsevier Ltd. All rights reserved.