黄河表层沉积物与稀土元素La~(3+)的交换吸附作用研究

采用现场采样及室内实验方法,研究了黄河表层沉积物与La^3 的交换吸附作用。结果表明,用Langmuir方程和Freundlich方程均能较好地反映La^3 在沉积物表面上的等温吸附过程,但以Langmuir方程拟合程度更好,黄河表层沉积物对La^3 的吸附强烈地受控于pH值在2-12这一宽广的pH范围内,La^3 黄河表层沉积物的交换吸附呈现随pH的增加而增大的总体趋势,在pH为2-7的范围内,随pH的增大,La^3 的吸附量逐渐增加,并在pH为6-7时达到最高值;当pH＞7时,随Ph的增大,La^3 的吸附量基本保持恒定,沉积物去除有机质后吸附能力下降了12.71%,与颗粒物中稀上元素有机物结合态所占比例相当.

Liquid -Solid Interface Interaction Between Surface Sediments and La3+in the Yellow River

Our study showed that Langmuir equation was mostly in accordance with the adsorption procedure, despite that Langmuir and Freundlich equation was fit. It has been also found pH value was the important factor in affecting the Yellow River sediment on adsorption of La3+ , the adsorption capacity of La3+ increase with the pH value increasing in the range of 2 to 12. The adsorption capacity of La3+ was up to the maximum when the pH value was from 6 to 7, and remained constant with the pH value increasing when the pH value more than 7. The adsorption capability decreased to 12.71% when organic matter in the Yellow River sediment was wiped off, and it was equal to the percentage of bound to organic matter of REEs in the Yellow River.