表生稀土矿区土壤中稀土元素的吸附特征

Adsorption of Rare Earth Elements in Soil of Supergence REE Mine

研究了赣南典型表生稀土矿区土壤中稀土元素的吸附特征及其主要影响因素。结果表明,稀土元素(La,Yb)的吸附过程符合Langmuir和Frendlich等温方程,稀土元素的吸附以可交换吸附为主。pH值是影响土壤中稀土元素吸附的极重要因素,随着pH值的增加,稀土吸附量增加。土壤去除有机质后,对稀土的吸附量下降约7.6％;去游离氧化铁后,稀土元素的吸附量增长7.4％左右。不同阴离子条件下,土壤对稀土元素的吸附量大小排序为:SO_4^(2-)>Cl^->NO_3^-。

Adsorption of rare earth elements (La, Yb) in soil of a typical supergence REE mine has been studied experimentally. The result showed that the adsorption proceeding of REE is fit for Langmuir and Frendlich equation, the exchangeable adsorption is the main form of REE adsorption ,pH is the important factor to effect adsorption of REE. While pH value increasing, the adsorption amount increased, especially at pH 5.0-6.0. The REE adsorption decreased about 7.6%when organic matter of soil was erased, but it increased about 7.4% when movable Fe-oxides of soil were erased. Effects of anion on REE adsorption have the sequence: SO42- > Cl- > NO3-.