Distribution coefficient determination of thorium on alluvium soil of Anarak Nuclear Repository

Calculation of distribution coefficients is one of the essential provisions in the safety assessment of radioactive waste repository and safe management of radioactive waste. Due to the importance and characteristics of thorium radionuclide in radioactive waste inventory, the distribution coefficient of thorium in the alluvium soil of Anarak Radioactive Waste Repository was determined by the Batch method two parameters of thorium concentration and soil granulation were studied. Also, the Flow-Through method studied the adsorption behavior of thorium has investigated the effect of thorium concentration and soil height. The average value of thorium distribution coefficient in Anarak soil was calculated 110960 L/kg using the Batch method. The study of adsorption behavior by the Flow-Through method demonstrated high uptake of thorium in the soil due to the strong bond created between the ion and the adsorbent. The results showed that the distribution coefficient increases with the decrease of soil particle size. Regarding the effect of concentration on the thorium distribution coefficient, first, an increasing trend and a decreasing trend were observed in the test range. The results obtained in this study were compared with the results of other studies on thorium radionuclide, which showed a good agreement with other studies.