Journal of Nuclear Science and Technology · 1984 · 13 citations · 3 references
Natural SciencesChemistryMaterials ScienceInorganic ChemistryPhysical ChemistrySurface ChemistryAdsorption At InterfacesCoordination ChemistryIon ExchangeMineral Surface ChemistrySurface AdsorptionBond Dissociation EnergiesInorganic SaltsIodine ChemistryIon AdsorptionIon Exchange ReactionsPhysical AdsorptionZeolite AdsorbentsZeolite Adsorption
Neutron activation technique was used to measure the amounts of I, Ag and Na elements in zeolite samples. The samples were nonradioactive before the activation analysis; this facilitated various operations to investigate the chemical form of the sorbed iodine. It was found that the Ag+ ions positioned in three types of sites react differently with iodine as follows: AgX·I2n, a physical adsorption product, released iodine immediately upon contact with water. (Agl)+ having a strong chemical bond did not release iodine either by heating or by submerging. (Ag…I)+ has a bond dissociation energy of several kcal·mor−1. When the sample was placed under water, part of the (Ag…I)+ ions released iodine very slowly and the remainder changed to thermally stable (AgI)+ ions. Ion-exchange reaction with aqueous sodium nitrate solution converted all of the (Ag…I)+ ions into stable AgI product. The Ag(3)+ions reside in the inaccessible site for I atoms. The ratio of the populations was determined as:
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