Cesium, thermodynamic data

According to the MD simulations examined for cesium iodide solutions of 2.78 mol dm-3 (Csl H20 = 1 20) at 25 and 64°C and 5.56 mol dm-3 (Csl H20 = 1 10) at 64°C (34), higher ion pairs than 1 1 form in the 2.78 mol dm-3 solution, but formation is suppressed as the temperature is raised. Thus, ion-pair formation reactions between cesium and iodide, both of which are weakly hydrated, must be exothermic, although no thermodynamic data are available in the literature. The increase in concentration at a given temperature (64°C) enhances the formation of the ionic aggregates from raCsI = 1.07 to 1.80. 

Although solvent samples have been observed for approximately one year without any solids formation, work was completed to define a new solvent composition that was thermodynamically stable with respect to solids formation and to expand the operating temperature with respect to third-phase formation.109 Chemical and physical data as a function of solvent component concentrations were collected. The data included BC6 solubility cesium distribution ratio under extraction, scrub, and strip conditions flowsheet robustness temperature range of third-phase formation dispersion numbers for the solvent against waste simulant, scrub and strip acids, and sodium hydroxide wash solutions solvent density viscosity and surface and interfacial tension. These data were mapped against a set of predefined performance criteria. The composition of 0.007 M BC6, 0.75 M l-(2,2,3,3-tetrafluoropropoxy)-3-(4-.sw-butylphenoxy)-2-propanol, and 0.003 M TOA in the diluent Isopar L provided the best match between the measured properties and the performance criteria. 

Vendilo, A.G. Ronkkomaki, H. Hannu-Kuure, M. Lajimen, M. Asikkala, J. Chernikova, E.A. Lajunen, L.H.J. Tuomi, T., Popov, K.I. (2009a) First Data on Thermodynamics of Complex Formation in Ionic Liquids Cesium Complexes with 18-Crown-6, Mendeleeo Comm., 19 196-197. 

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