长江口沉积物对铅的吸附作用

Adsorption of lead on sediment from Changjiang Estuary

模拟研究长江口悬浮沉积物对 Ｐｂ的吸附作用，发现沉积物的吸附性能与其氧化铁和有机物等活性组份的含量密切相关。获得Ｌａｎｇｍｕｉｒ型吸附等温线。测定他和吸附容量和分配系数。结果表明，ｐＨ和盐度对吸附产生明显影响。吸附率与ｐＨ和盐度之间分别呈线性正相关和负相关关系。初步探讨吸附动力学特征。沉积物对Ｐｂ吸附以化学作用为主，与厦门港沉积物相似。

The adsorption of lead by suspended sediments from Changjiang Estuary is simutated. The suspensed sediment shows high adsorption potential to lead with xm≈2×10^-3 (m/m) and K^d≈1×10~4cm^3/g. The Langmuir adsorption isotherm have been determined. The ad sorption of Pb by sediment is essentially a chemical action; The salinity and pH significantly influenced the adsorption fraction, being α(%)=-0. 885+94.6 and α(%)=23. 6pH-115; The adsorption of sediment-Pb is quick and the adsorption equilibrium is essentially reached within 2~3h. The adsorption processes can be discribed by the exchange equilibrium kinetic model.