In the theoretical part of this study, the thermodynamics of ionic hydration was considered. Hydration functions were assumed to consist of neutral and electrostatic terms. Neutral contributions were evaluated from noble gas solubility data. Mean Spherical Approximation equations, combined with the Stillinger ST-2 off-centered water dipole model, supplied values for the electrostatic functions. Calculated Gibbs free energies of hydration for several ions agreed with experiment. Discrepancies between the calculated and absolute values of entropies of hydration can be correlated with the structure breaking tendency of monovalent ions. / A tracer level solvent extraction technique was used to investigate ionic interactions in aqueous electrolytes. Am(III) was chosen as a test metal ion and a cation exchanger HDEHP as the extractant. From the activity coefficients, calculated by Pitzer's theory, and measured distribution ratios it was deduced that the ion pairing of Am(III) in single electrolytes with anion X('-) (X('-) is ClO(,4)('-), NO(,3)('-) and Cl('-)) first increases with the concentration of X('-), then decreases and finally rises again. The salting out phenomenon at intermediate concentrations was attributed to the energetically unfavored co-sphere overlap between Am(III) and X('-). / The extraction of Am(III) from constant ionic strength (1.00, 2.50 and 5.00 M) electrolyte mixtures was analyzed by the stability constant technique. Stoichiometric first stability constants for AmNO(,3)('2+) and AmClO(,3)('2+) were determined. Problems with the evaluation method were also discussed. As an alternative treatment of the data, an empirical equation of the form DELTA = i(,2)(1 - i(,2)) (u + (1 - 2i(,2))v was introduced, where DELTA is proportional to the reciprocal of the distribution ratio. Variation of the interaction parameters u and v can be interpreted in terms of the thermodynamic properties of the medium ions. Except when DELTA varies about zero, u and v vary consistently with the ionic stength, which allows for predictions of distribution ratios at untested ionic strengths and composition. / Source: Dissertation Abstracts International, Volume: 48-03, Section: B, page: 0776. / Thesis (Ph.D.)--The Florida State University, 1987.
| Identifer | oai:union.ndltd.org:fsu.edu/oai:fsu.digital.flvc.org:fsu_76097 |
| Contributors | ROSTA, LASZLO., Florida State University |
| Source Sets | Florida State University |
| Detected Language | English |
| Type | Text |
| Format | 168 p. |
| Rights | On campus use only. |
| Relation | Dissertation Abstracts International |
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