Quasi-elastic neutron scattering was used to study water adsorbed at different concentrations in BaX zeolite. It was found that, the lower the water content, the higher the temperature which was required to reach adsorption equilibrium. For a loading of 15 molecules per supercage, an evolution of the QENS intensity with time was observed at 440K which suggests that the sample was not in equilibrium; for a loading of 10 molecules per supercage, this happens at 520K. Even at the highest studied temperature, 520K, the diffusion coefficient of water in the equilibrated samples was lower than 10-12m2/s. This was much lower than in NaCaA zeolites, manifesting the very large interaction between water and the Ba cations.

On the Adsorption and Diffusion of Water in BaX Zeolite. H.Jobic, A.Méthivier, T.Seydel: Comptes Rendus Chimie, 2005, 8[3-4], 411-7