Carbon monoxide, dinitrogen and carbon dioxide adsorption on zeolite H-Beta: IR spectroscopic and thermodynamic studies

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 Brønsted acid sites was found to involve an enthalpy change of −27, −19 and −33 kJ mol−1 for CO, N2 and CO2, respectively; the corresponding entropy change was −150, −140 and −146 J mol−1 K−1. The adsorbed gases showed also a weak interaction with silanols, which involves a ΔH0 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.

► Variable temperature IR spectroscopy is used to study adsorption of CO, N2 and CO2 in the protonic zeolite H-Beta. ► By simultaneously recording IR absorbance, temperature and equilibrium pressure, standard adsorption enthalpy and entropy for each gas was determined. ► The results are discussed in the broader context of gas separation using zeolites; focusing on carbon dioxide capture.