黄泥土中胡敏酸对芘的吸附及作用机理研究

采用高效液相色谱法测定了3种不同利用方式下黄泥土中胡敏酸对芘的吸附效应，并利用元素分析、FTIR图谱分析对其吸附机理进行研究。吸附试验表明，桑园、水田、水杉土壤中胡敏酸对芘的吸附在低浓度范围近似线性，而浓度较高时，吸附曲线的非线性增强，三者呈相似的非线性吸附。不同利用方式下黄泥土中胡敏酸对芘的吸附等温线用Freundlich等温方程拟合效果很好，均达到显著相关。元素分析与FTIR图谱分析结果表明，10年时间的不同利用方式对土壤中胡敏酸元素组成影响较小；桑园、水田、水杉土壤中胡敏酸对芘的吸附分配系数有一定差别，推测脂肪族类物质对吸附起着重要的影响。由胡敏酸吸附前后的FTIR图谱变化主要集中在3400、2920cm^-1附近，进一步推出两者结合机制是胡敏酸中脂肪族类物质作用的结果。

Adsorption of Pyrene by Humic Acids Extracted from Huangnitu and the Interaction Mechanism

The adsorption of pyrene by HAs extracted from three different use types (mulberry field, paddy field, metasequoia field) of Huangnitu soil under was determined by using high performance liquid chromatography (HPLC, Waters 2690,Waters, Milford, MA) method. The adsorption phenomenon and mechanism were also analyzed by Elemental analysis and FTIR spectra. The results indicated that the sorption isotherms of pyrene in different HAs all showed nonlinear sorption from the whole curves, with almost linear in lower density but nonlinear in higher density. Pyrene adsorption to three HAs could be well fitted by Freundlich isotherms with significant correlation. Elemental analysis and FTIR spectra showed that different use types of soil for ten years had small influences on element composition of HAs, but the adsorption partition coefficients were different under three types of soil use, which suggested that the different sorption power was concerned with their composing structures, aliphatics might play an important role in binding and determined the sorptive power of pyrene in HAs.