【作者】 娄保锋；

【导师】 朱利中；

【作者基本信息】 浙江大学 ， 环境科学， 2004， 博士

【摘要】 有机污染物在土壤／沉积物上的吸附和脱附行为会影响它们在自然环境中的迁移、转化、归宿和生物生态效应。而且这种行为也会受到有机污染物本身的物理化学性质、吸附剂的组成和结构、环境条件及共存有机污染物等多种因素的影响。目前，对吸附机理及影响因素认识的局限性，使得有机污染物的迁移转化和归宿模型在实际水环境中的预测存在较大的误差。在用水质模型进行水质预测时，对有机污染物在悬浮颗粒物／沉积物上的吸附作用考虑不够，使预测结果常与实际值有较大的偏差，不利于水污染控制和水环境管理。所以，有必要更加深入地研究有机污染物的吸附／脱附作用，及其对水质预测的影响。本文评述了有机污染物在土壤／沉积物上吸附作用的研究进展，在此基础上研究了有机污染物在沉积物上的吸附机理及影响因素，并对河流水质模型进行了改进。 论文主要取得了以下研究成果。(1)有机化合物的吸附竞争能力与其物化性质具有相关性，易与沉积物有机质形成氢键的化合物其竞争能力也比较强；(2)可离子化有机化合物的吸附竞争能力与其存在形态有关。酚类、含苯环的羧酸类化合物(有机酸)，其离子态的吸附竞争能力远小于分子态，其机理为有机酸阴离子所带的负电荷抑制了表面吸附能力，主要发生分配作用；而苯胺类化合物(有机碱)，其离子态和分子态都表现出显著的竞争能力，而且离子态的竞争能力略强于分子态，原因在于有机碱阳离子所带的正电荷促进了其表面吸附能力；有机化合物竞争能力的强弱与其单组分吸附等温线的非线性程度具有一定的相关性，吸附等温线近似为线性的化合物没有或只具有微弱的竞争能力；(3)对目标有机化合物的吸附具有竞争效应的有机化合物(作为共溶质)混合后，将对目标有机化合物的吸附产生协同竞争效应；(4)以京杭运河为例，率先提出了将有机污染物的吸附／脱附作用及水文水力参数耦合到水质模型中的方法，并讨论了吸附／脱附作用对不同有机污染物预测模型的影响，为建立更准确的水质模型及进行更客观的风险和生态评估提供了参考依据。更多还原

【Abstract】 Sorption/desorption of organic pollutants with soil/sediment plays an important role in their transport, fate and bioavailability in natural environment. Sorption and desorption of organic compounds are also influenced by such factors as its physico-chemical properties, constituents and construction of sorbents, environmental conditions and coexistent organic compounds. Presently, knowledge of sorption and desorption is limited, which results in significant errors in environmental prediction of organic compounds. Also, ignoring sorption/desorption of organic pollutants with suspended solids and sediments often make prediction results of water quality model deviate significantly from observations. Therefore, it is needed for researchers to study deeply sorption/desorption of organic compounds and incorporation of them into water quality mode. Based on review on sorption/desorption of organic pollutants with soil/sediment, mechanisms and influential factors of sorptrbn/desorption were investigated deeply.The results of the present research are as follows, (i) The correlation between physico-chemical properties of organic compounds and their competitive power was studied, and it was indicated that organic compounds preferable to form H-bonding with organic matter of sorbents have stronger competitive power; (ii) Sorption behaviors of ionizable organic compounds in different species and their competitive power were examined, and the results showed that phenols and carbonxylic acids with benzyl circle have much stronger competitive power in molecular species than in ionized species, because negative charges of anionic forms can depressed their adsorption on the surface of the sediment; in contrast, organic bases such as aniline and p-chloroaniline show weaker competitive power in molecular species than in ionized species, and this is because both species of the organic bases could adsorb strongly onto the sediment; there is a correlation between competitive power of organic pollutants in multi-solute systems and their sorption isotherm nonlinearity in single-solute systems, and organic compounds whose sorption isotherms is linear in single-solute systems hardly have competitive power in multi-solute systems; (iii) Competitive sorption effects in more than two-solutes systems was studied, and it was exhibited that mixture of two cosolutes each of which could suppress sorption of nominal solute onto the sediment had synergistically competitive sorption effect on the nominal solute; (iv) A method about incorporating sorption/desorption of organic pollutants into river water quality model was developed, and discussion about degree of sorption/desorption effect on model prediction for different organic compounds was made, which will provide theoretical basis and practical processes for setting up more accurate water quality model.更多还原