137Cs Sorption on the Loams of the Republic of Belarus

It was established that the content of the main clay minerals in the loam sample from the Fanipolskoye deposit is 13.6 wt % for montmorillonite and 3.3 wt % for illite. It was determined that the pH of solution in the range of 4–12 has virtually no effect on 137Cs+ sorption by the loam. The distribution coefficient (Kd) of 137Cs for the specified loam sample with a K+ concentration in the solution of up to 0.01 mol/dm3 is higher than 103 dm3/kg, which indicates that the 137Cs sorption is efficient. The loam contains two types of sorption sites, T1 and T2, with different selectivity and capacity toward Cs+. The sorption capacities of sites T1 and T2 for Cs are 4.0 × 10–5 and 1.2 × 10–2 mol/kg, respectively, and the values of Kd of Cs for these sites differ by a factor of 20 and are 1.6 × 104 and 7.9 × 102 dm3/kg. The loam from the Fanipolskoye deposit is shown to be suitable as a buffer backfill for the disposal site of very low-level radioactive waste from the Belarusian NPP.