Ni Jin-zhi, Luo Yong-ming, Wei Ran, Li Xiu-hua, Qian Wei
Soil and Environment Bioremediation Research Centre, Institute of Soil Science, Chinese Academy of Sciences, Nanjing 210008, China.
Huan Jing Ke Xue. 2008 Dec;29(12):3531-6.
Sorption and desorption of phenanthrene by organo-mineral complexes with Ca2+, Fe3+ and Al3+ as bridge cations were studied according to the association type between organic matter and minerals in natural soils. The results showed that the data of phenanthrene sorption and desorption by different cation saturated montmorillonite and their corresponding humic acid and mineral complexes could be fitted with Freundlich model, and the order of the sorption capacities (Kf) were Ca-Mont (0.184) > Fe-Mont (0.028) > Al-Mont (0.015) and Fe-Mont-HA (2.341) > Ca-Mont-HA (1.557) > Al-Mont-HA (1.136), respectively. The Kf values of humic acid and mineral complexes were far greater than those of minerals, which demonstrated that humic acid made great contributions to the sorption of phenanthrene in the organo-mineral complexes. However, the Kf values of the organo-mineral complexes with different bridge cations were not consistent with their organic carbon content, which indicated that both the organic carbon content and the combined types between organic matter and mineral could affect the sorption capacity of phenanthrene by the organo-mineral complexes. The desorption hysteresis of phenanthrene was significant for Ca2+ and Al3+ bridged organo-mineral complexes. Desorption hysteresis of phenanthrene was mainly from the sorption of phenanthrene by organic matter, and the contributions of mineral to the desorption hysteresis were not significant.
根据天然土壤中有机质与矿物质之间的结合类型，研究了以Ca2+、Fe3+和Al3+作为桥接阳离子的有机-矿物复合体对菲的吸附和解吸作用。结果表明，不同阳离子饱和蒙脱石及其相应的腐殖酸和矿物复合体对菲的吸附和解吸数据均能较好地拟合Freundlich模型，吸附容量（Kf）顺序分别为：Ca-蒙脱石（0.184）＞Fe-蒙脱石（0.028）＞Al-蒙脱石（0.015），以及Fe-蒙脱石-腐殖酸（2.341）＞Ca-蒙脱石-腐殖酸（1.557）＞Al-蒙脱石-腐殖酸（1.136）。腐殖酸和矿物复合体的Kf值远大于矿物的Kf值，表明腐殖酸对有机-矿物复合体中菲的吸附有很大贡献。然而，不同桥接阳离子的有机-矿物复合体的Kf值与其有机碳含量不一致，这表明有机碳含量以及有机质与矿物之间的结合类型均会影响有机-矿物复合体对菲的吸附能力。对于Ca2+和Al3+桥接的有机-矿物复合体，菲的解吸滞后现象显著。菲的解吸滞后主要源于有机质对菲的吸附，矿物对解吸滞后的贡献不显著。
