Radiocesium Sorption on Soils and Clay Minerals: Effect of Oxalates and Sodium Tetraphenylboron

The knowledge on radiocesium behavior in soils is important for devising effective strategies and techniques to minimize its transfer to plants. In the present investigation, adsorption-desorption of radiocesium in soils and clay minerals as influenced by oxalate and sodium tetraphenylboron was studied. Twelve soils representing different soil orders and seven pure clay minerals representing distinct clay mineral groups were used for the present study. In general it was observed that more than 90% of Cs-134 was adsorbed on soils and clays even under the influence of competing solutions like sodium oxalate. On an average the adsorption of Cs-134 were comparatively higher in soils with neutral to alkaline pH. Among the clay minerals the adsorption was minimum for kaolinites (kaolinite and halloysite). The desorption studies using sodium oxalate shows that, in general with an increase in concentration of the extractant, the total Cs desorbed also increases. Sodium tetraphenylboron was found to remove higher radiocesium from clay minerals. Desorption was maximum in laterite and red soils and amongst clays, kaolinites showed almost similar trend.