污染土壤颗粒中钚的结合形态

Chemical Species of Plutonium in the Contaminated Soil Particles

在我国北方某处荒漠土中掺入氧化钚后制备模拟土壤,湿法粒度分级后,利用改进的Tessier连续提取法研究各粒级土壤颗粒中钚的结合状态,以评价在假想的污染状况下钚在该类区域土壤中的迁移性。结果表明,钚与土壤的结合主要为有机结合态和残渣态(73%～96%)。各粒级中钚的结合状态与土壤颗粒有机质及伊利石含量呈现良好的线性关系。可交换态钚含量小于0.8%,表明氧化钚在该类土壤中的迁移性很弱。

APuOz was mixed with soil samples collected at a desert region in northern China. The mixture was classified with wet classification method and an improved Tessier＇s sequential extraction method was applied to study the species of Pu in the contaminated soil particles, in order to evaluate the mobility of Pu at this site under supposed conditions. It is found that major part （about 73%-960//00） of Pu is bounded to organic materials and existed as residual forms. There was a obvious linear relationship between the percentage of Pu species and the amount of organic material or illite. Less than 0. 8% of Pu exists in exchangible form. The results show that Pu is difficult to migrate in such area.