^(110m)Ag和^(137)Cs在海洋沉积物中分配系数研究

Study on Adsorption Distribution Coefficients of ^(110m)Ag and ^(137)Cs on Offshore Sediment

采用静态批式法研究了吸附时间、固体浓度及核素浓度对放射性核素110mAg和137Cs在海洋沉积物中分配系数的影响。结果表明,110mAg在海洋沉积物中的吸附平衡时间约7天,137Cs在海洋沉积物中的吸附平衡时间约10天;在低浓度条件下110mAg和137Cs在海洋沉积物中的吸附等温线趋近于线性,即核素分配系数不随核素浓度的增加而改变;当固体浓度在0.25~10 g/L时,两核素分配系数均随固体浓度的增加明显减小,而固体浓度达到一定上限后(>10 g/L),核素分配系数不再随固体浓度的增加而改变。

The adsorption distribution coefficients of ^110mAg and ^137Cs on offshore sediment were studied by batch experiments. The factors that affected adsorption experiment were adsorption time,particle concentration and initial radioactivity concentration. The results showed that,the adsorption of ^110mAg and ^137Cs were quickly to achieve the sorption equilibration,the time of ^110mAg to achieve the adsorption equilibrium was about 7 days, ^137Cs was 10 days. The adsorption isotherms of ^110mAg and ^137Cs in marine sediments tend to be linear. The distribution coefficients did not seem affected with the rising of initial radioactivity concentration. But the values of distribution coefficient were decreased while particle concentrations were increasing between 0. 25 - 10 g/L.