Cesium adsorption behavior of vermiculite and it's application to the column method

The cesium adsorption behavior of vermiculite from a pure aqueous solution was studied in terms of the vermiculite grain size and reactant concentrations. Although a relation between grain size and the cesium adsorption percentage was not observed when the concentration of cesium in the reactant was high, the adsorption rate decreased at a certain grain size when cesium concentration was low. Reverse ion-exchange reactions were insignificant when water was used as an eluent. Vermiculite with a grain size of 500-599 μm was used in the column method. As the flow rate increased, the breakthrough point decreased. Although a considerably low flow rate was required to obtain significant recovery of cesium from contaminated water, it is suggested that vermiculite with a relatively large grain size could be used in the column method. (author)