Adsorption and Desorption of Radiocesium on Some Soils of India

Radiocesium adsorption and desorption on some soils representing seven soil orders of India was studied to evaluate the effect of time of contact, activity level, potassium activity ratio and supporting electrolytes. ¹³⁴Cs sorption on soils was rapid and near equilibrium was reached in 30 minutes of contact time. ¹³⁴Cs sorption varied from 78 to 99%, the maximum being in Vertisols and Inceptisols. The sorption on soils was greatly influenced by ¹³⁴Cs activity levels i.e. decreased with increasing ¹³⁴Cs activity. Higher activity ratio of potassium decreased the radiocesium sorption on soils. Soils dominated with 2:1 type minerals (smectite and micaceous minerals) exhibited higher adsorption. ¹³⁴Cs desorption from soils was significantly higher with NH₄Cl and KCl extractants.