| Abstract
| - Silver is known to strongly affect the adsorptive properties of some zeolites. It is alsoknown that thermal vacuum dehydration of some argentiferous zeolites leads to the formationof charged silver clusters within the zeolite. In this work we have synthesized silver zeolitesof the types Y, X, and low-silica X. The zeolites were treated in such a way as to promotethe formation of intracrystalline charged silver clusters. Equilibrium room-temperatureisotherms were measured for adsorption of nitrogen for each of the zeolites after variousheat treatments and dehydration. These materials were structurally characterized viaRietveld refinement using neutron powder diffraction data. Color changes upon heattreatment and subsequent X-ray photoemission spectroscopy confirmed some reduction ofAg+ → Ag0. The effects of various dehydration conditions, including the time, temperature,and atmosphere, on the room-temperature adsorption of nitrogen are discussed. Structuralcharacterization, along with valence bond calculations, revealed the presence of cations insite II*, which are more active in Ag−LSX samples that were vacuum dehydrated at 450 °Cas compared to those that were vacuum dehydrated at 350 °C.
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