Specific ionic interactions and solubility activity product of caesium perrhenate at 298.10 K

Abstract

The solubilities of caesium perrhenate in aqueous CsCl, NaCl, KCl and KReO4 solutions at 298.10 K are reported. The solubility activity product for CsReO4 was determined by using extrapolation functions involving two different mean ionic activity coefficient expressions and the results were compared; the total ionic strengths of all the saturated perrhenate solutions were less than 0.1 mol dm-3. One of these expressions used is that proposed recently by Panckhurst and Macaskill1,2 which is an extension of Guggenheim's approach,3,4 specific ionic interactions in aqueous solutions being explicitly taken into account. Its use led to more consistent values for the solubility activity product for CsReO4 than those obtained with the other expression which does not incorporate specific interaction parameters. Values of specific ionic interaction parameters for caesium, potassium and sodium perrhenates in dilute aqueous mixtures with CsCl, KCl, KReO4, KI or NaCl are also reported.