Wang Ying, Shen Zhenyao, Niu Junfeng, Liu Ruimin
School of Environment, Beijing Normal University, Beijing 100875, People's Republic of China.
J Hazard Mater. 2009 Feb 15;162(1):92-8. doi: 10.1016/j.jhazmat.2008.05.013. Epub 2008 May 9.
The adsorption of phosphorus (P) on four sediment samples (CunTan, XiaoJiang, DaNing and XiangXi) from the Three-Gorges Reservoir on the Yangtze River in China was studied systematically in batch experiments. A sequential chemical extraction experiment was conducted to clarify the effect of sediment composition on P adsorption. The results showed that P adsorption on four sediment samples mainly occurred within 6h. P adsorption kinetics can be satisfactorily fitted by both power function and simple Elovich model. A modified Langmuir model may describe well the P adsorption on all the samples in our study. Theoretically, the maximum adsorption amount (Q(max)) was 0.402mg-P/g for XiaoJiang sediment, 0.358mg-P/g for DaNing sediment, 0.165mg-P/g for CunTan sediment, and 0.15mg-P/g for XiangXi sediment. The sediment compositions such as organic matter, metal hydroxides, calcium and clay content showed influences on the P adsorption. Wherein, organic matter and metal hydroxides were the main factors affecting the P adsorption. The maximum P adsorption capacity (Q(max)) enhanced with the increase of the content of (Fe+Al+Ca). Compared the zero-equilibrium P concentration (EPC(0)) values obtained by the modified Langmuir models with actual P concentrations in water, all the sediments studied in this paper except for XiaoJiang showed a trend of releasing P as a source role, which could enhance the risk of eutrophication occurrence in the Three-Gorges Reservoir.
采用批量实验方法，系统研究了长江三峡水库4种沉积物样品（寸滩、小江、大宁和香溪）对磷（P）的吸附作用。通过连续化学提取实验，阐明沉积物组成对磷吸附的影响。结果表明，4种沉积物样品对磷的吸附主要在6h内完成。磷吸附动力学能较好地用幂函数和简单的埃洛维奇模型拟合。修正的朗缪尔模型能较好地描述本研究中所有样品对磷的吸附。理论上，小江沉积物的最大吸附量（Q(max)）为0.402mg-P/g，大宁沉积物为0.358mg-P/g，寸滩沉积物为0.165mg-P/g，香溪沉积物为0.15mg-P/g。沉积物组成如有机质、金属氢氧化物、钙和黏土含量对磷吸附有影响。其中，有机质和金属氢氧化物是影响磷吸附的主要因素。最大磷吸附容量（Q(max)）随（Fe+Al+Ca）含量的增加而增大。将修正的朗缪尔模型得到的零平衡磷浓度（EPC(0)）值与水体中的实际磷浓度进行比较，结果表明本文研究的除小江外的所有沉积物均表现出作为磷源释放磷的趋势，这可能会增加三峡水库发生富营养化的风险。
