中文摘要：

建立并验证了腐植酸（HA）和芘结合常数（Koc）测定的荧光猝灭法，进而研究了重金属离子对HA和芘相互作用的影响，测定了重金属离子存在FHA和芘之间的Koc结果表明：纯化后的HA是分子质量较小的部分，水溶性较高，具有羟基、羧基和碳氧键等极性基团；HA利用其分子中的羟基、羧基、碳氧键等基团和重金属离子产生络合作用，这种络合作用影响了HA的结构；随着重金属离子浓度的增大，Koc遵循先增大，再减小，最后趋于不变的趋势。

英文摘要：

The fluorescence quenching method for study on the interaction between humic acid （HA） and pyrene was developed and validated. The complexation between HA and Cu^2＋ , Fe^2＋ and Ni^2＋ were studied by Infrared spectroscopy. The effects of heavy metal ions on the interaction between HA and pyrene were investigated by the established method. The results showed that the humic acid was the lighter part of the whole molecule and had high aqueous solubility after purified. The binding sites of HA and heavy metal ions located in the carboxyl and hydroxyl of HA. The complexation changed the HA structure, the binding constant （Koc） between HA and pyrene obeyed a same trend in which with the increment of heavy metal ions, Koc increased firstly, and then decreased, finally reached a stable value. The reasons may be explained as the complexation and charge neutralization between HA and heavy metals.