多环芳烃在天然水体中的自净机理研究——沉积物对多环芳烃的吸附过程模拟

Study on self purification mechanism for PAHs in natural water system —modelling of adsorption process for PAHs on sediments

以黄浦江、淀山湖底泥为沉积物的代表，蒽为多环芳烃的代表性化合物，研究了多环芳烃在天然水体中沉积物上的吸附机理。结果表明，实验条件下两种底泥对蒽的吸附均属多分子层吸附，可用ｄｅＢｏｅｒ－Ｚｗｉｋｋｅｒ公式所表示的极化模型较好地描述；吸附等温线出现的阶梯是由于蒽－甲醇分子的溶剂化作用及底泥颗粒的表面不均匀性所致；未参与溶剂化作用的甲醇与溶剂化蒽分子间存在竞争吸附；固体疚应对吸附容量存在较大的影响。

The sediments in Huangpu River and Dianshan Lake were chosen and anthracene was a model compound of PAHs in the research.The results show that the adsorption type of mathracene on sediments is multi molecular layer adsorption,which can be well described by de Boer Zwikker Equation for polarization model.It is believed in thes research that the stepwise adsorption isotherm curves are caused by anthracene methanol solvolytes and the uneven surface of sediment particles.There is a competitive adsorption on sediments between non solvolytic methanol molecules and anthracene methanol solvolytes.In the adsorption process,the adsorption capacity of anthracene is affected by the concentration of solid.