Ran Yong, Huang Weilin, Rao P S C, Liu Dehan, Sheng Guoying, Fu Jiamo
State Key Laboratory of Organic Geochemistry, Guangzhou Institute of Geochemistry, Chinese Academy of Science, Wushan, Guangzhou 510640, China.
J Environ Qual. 2002 Nov-Dec;31(6):1953-62. doi: 10.2134/jeq2002.1953.
This study examines the effect of soil organic matter heterogeneity on equilibrium sorption and desorption of phenanthrene, naphthalene, 1,3,5-trichlorobenzene (1,3,5-TCB), and 1,2-dichlorobenzene (1,2-DCB) by soils and sediments. Two estuary sediments, a Pahokee peat (PP; Euic, hyperthermic Lithic Haplosaprist), and two subsamples (base- and acid-treated peat [TP] and acid-treated peat [FP]) of the peat were used as the sorbents. The contents of black carbon particles were quantified with a chemical extraction method. Petrographical examinations revealed the presence of the condensed soil and sediment organic matter (SOM) in Pahokee peat. The Freundlich isotherm model in two different forms was used to fit both sorption and desorption data. The results show that the sorption and desorption isotherms are generally nonlinear and that the apparent sorption-desorption hysteresis is present for phenanthrene and TCB. Detailed analysis of sorption data for the tested sorbent-sorbate systems indicates that black carbon is probably responsible for sorption isotherm nonlinearity for the two sediments, whereas the humic substances and kerogen may play the dominant role in nonlinear sorption by the peat. This investigation suggests that the microporosity of SOM is important for the hydrophobic organic contaminant (HOC) sorption capacity on the peat.
本研究考察了土壤有机质非均质性对土壤和沉积物对菲、萘、1,3,5-三氯苯（1,3,5-TCB）和1,2-二氯苯（1,2-DCB）的平衡吸附和解吸的影响。使用两种河口沉积物、一种帕霍基泥炭（PP；富铁、高热性石质高腐殖质土）以及该泥炭的两个子样本（碱处理和酸处理泥炭[TP]以及酸处理泥炭[FP]）作为吸附剂。采用化学萃取法对黑碳颗粒含量进行了定量分析。岩相学检查揭示了帕霍基泥炭中存在缩合态土壤和沉积物有机质（SOM）。使用两种不同形式的弗伦德利希等温线模型对吸附和解吸数据进行拟合。结果表明，吸附和解吸等温线通常是非线性的，并且菲和三氯苯存在明显的吸附-解吸滞后现象。对测试的吸附剂-吸附质体系的吸附数据进行详细分析表明，黑碳可能是导致两种沉积物吸附等温线非线性的原因，而腐殖物质和干酪根可能在泥炭的非线性吸附中起主导作用。本研究表明，SOM的微孔性对于泥炭对疏水性有机污染物（HOC）的吸附能力很重要。
