The composition of mixed micelles and mixed micelle — solution interfaces changes with the concentration and molar ratio of the cationic and anionic surfactants present. The micelle — solution interface includes besides the headgroups of both surfactants, the counterions of the surfactant in excess. The finding of an enhanced binding of counterions to mixed micelles may be of some practical importance in decontamination.
Authors:N. Filipović-Vinceković, Lj. Brečević, and D. Kralj
The sorption of cesium and cobalt on kaolinite and montmorillonite were followed by radiotracer method. The sorption of cesium can be described by a Freundlich isotherm. Cobalt sorption on clays equilibrated in cesium chloride solutions significantly differs for kaolinite and montmorillonite due to their differences in sites available for cation sorption and changes in solution chemistry.Heterogeneous exchange of cesium ions between clay and the surrounding electrolyte was performed in order to obtain information about clay/electrolyte systems equilibration. An interplay of different processes included in the attainment of true chemical equilibria of clay/electrolyte systems are responsible for the change of clay surface properties and total exchange capacity.
Authors:N. Filipović-Vinceković, D. Barišić, N. Mašić, and S. Lulić
The distribution of137Cs through soil layers has been investigated by field sampling. The investigation deals with137Cs concentration found after the Chernobyl accident. The relationship between important soil characteristics, total precipitation and cesium distribution are analyzed. Cesium is strongly sorbed in the top soil layer and its migration downward is limited. Measurements performed over a 3-year period revealed that approximately 20–38 per cent of total137Cs is located in the upper soil layer.
Authors:N. Filipović-Vinceković, V. Tomašić, N. Nekić, and M. Široki
The influence of long-term interactions on sorption of cesium on montmorillonite has been examined. After initial fast sorption due to ion-exchange, the additional two-step sorption as a result of dissolution of main clay constituents, changes in solution chemistry and readsorption and/or precipitation of resultant species, were observed.