某极低放填埋场土壤对Co吸附行为的初步研究

Preliminary Study on the Adsorption Behavior of Co in the Soil of A Landfill for Very Low-level Radioactive Waste

通过核素在土壤中的吸附行为研究为填埋场环境影响评价提供技术支持,运用批试法研究了不同物理条件下,土壤对Co的吸附。研究结果表明:吸附平衡时间为5天左右,土壤对Co的吸附模式符合Freundlich模式;酸性条件下,土壤对Co吸附能力较弱,pH从7开始增大,吸附比随之急剧升高;土壤粒径、液固比对土壤关于Co吸附比的影响不大,但随着液固比增大,吸附效率明显降低;共存的Ca2+能明显减弱Co在土壤中的吸附。

Technical supports could be got for the environmental impact assessment for the landfill by the investigation on adsoption of radionuclides in soil.Both experiments were carryied out to investigate the adsorption behavior of Co in the soil under different physical conditions.The results showed that adsorption equilibrium time was 5 d,the adsorption on Co for soil fit the Freundlich model,the adsorption was weak under acidic conditions,but the Kd increased sharply when pH began to increase from 7,soil particle size and liquid-solid ratio had little effect on the Co adsorption ratio of soil,but with the liquid-solid ratio increased,the adsorption efficiency decreased,and coexistence of Ca2＋ could significantly reduce the adsorption of Co in soil.