The adsorption behavior of cesium on pure minerals is reviewed. Although this field has been investigated intensively, the data are extremely variable in scope and interpretation with detailed information being available for only a few minerals. In current investigations in this field, the emphasis is on the nature of the adsorption sites and identification of these sites using spectroscopic techniques. In the first section of this review, the general mechanism of cesium adsorption is discussed and this is followed by consideration of the effect of parameters such as cesium concentration, the properties of the mineral and the characteristics of the solution phase, on cesium adsorption. Finally, interaction of cesium with some different minerals is described in some detail.
Batch sorption experiments using nickel have been carried out on marl, a sedimentary, carbonaceous rock. All experiments were performed with a synthetic water of pH 7.3 and in an atmosphere of N2/1% CO2. Over the equilibrium nickel concentration range of 10–11–10–5M, sorption was linear and reversible with Rd of 819 ml g–1. Owing to the linear sorption behavior, Rd was independent of rock/water ratio (r/w=1/5–1/100). The data suggested that at [Ni] lower than 10–7M an isotope exchange mechanism operated, whereas at higher [Ni], sorption involved ion exchange. Sorption experiments on some of the components of marl indicated that nickel adsorbs mainly on the clay minerals and on the trace of iron hydroxide present; sorption on calcite and quartz was low.