Additivity of the distribution ratio of Cs and Se on bentonite/quartz sand mixture in seawater

Summary

To provide comprehensive information for assessing the safety of geological disposal of radioactive waste, the additivity of sorption properties during different reaction times for various bentonite/quartz sand mixtures was investigated. Se and Cs were the nuclides of interest. Synthetic seawater (SW) was employed as the liquid phase tosimulate the possible groundwater conditions while the disposal site is an island area. Batch sorption experiments were conducted to measure the distribution ratio, R _d. Regardless of whether Cs and Se were used, the additivityat the reaction time of 7 and 14 days was better than that of 28 and 56 days.Interactions between bentonite and quartz sand might occur in synthesized seawater in reactions beyond 14 days. Under the experimental conditions,the additivity equation could be corrected by the composition ratio and reaction time. Long-term prediction of the R _dby short term batch sorption experiments would be helpful while assessing buffer materials mixed by bentonite and quartz sand.