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水体富营养化已成为世界性的水环境污染问题，而磷是导致水体富营养化的关键性限制因子，其过量输入对水生生态系统和人体健康产生严重危害。因此，如何有效降低富营养化水体中磷酸盐的负荷已成为环境领域的研究热点。大量研究表明，当淡水湖库外源磷得到有效遏制后，沉积物中磷在特定环境条件下会发生“二次释放”，仍可长期维持水体富营养化。因此，对受污染水体与沉积物中内负荷磷的科学控制是水体富营养化治理的重要内容。吸附法与原位钝化法是目前针对富营养化水体和沉积物磷污染修复的两种主要技术。蒙脱石作为一类具有天然纳米特征的无机超高分子量硅酸盐聚合物，因其比表面积大、孔隙多及优良的表面吸附性和离子交换性，在环境污染治理中被广泛应用。锆氧化物物化性质稳定、水溶性低、无毒害，且对磷酸盐有强烈的吸附能力。因此，探索采用锆改性天然蒙脱石，并将其应用于地表水体及沉积物中磷的污染控制是一种创新性的尝试。本论文表征了主要产地、不同类型蒙脱石的性能参数，遴选出适宜的蒙脱石基质，进而采用表面交联法制备锆改性蒙脱石吸附剂，开展其对受污染水体和湖库沉积物磷的控制实验研究，主要取得了如下几点成果和认识：（1）所选内蒙钙基蒙脱石呈弱碱性、纯度高、层间距适中，阳离子交换容量较高，且对水体磷酸盐具有一定的吸附作用，适宜于作为基质材料制备蒙脱石改性吸附剂。（2）综合利用XRD、SEM-EDS、XRF等检测手段对所制备的锆改性钙基蒙脱石进行表征。结果显示，锆成功地负载在钙基蒙脱石表面及层间域，蒙脱石的部分层间结构受到一定程度的破坏。锆的负载量随着锆源添加比例的增加而增加，系列改性吸附剂Zr-CaM0.1、Zr-CaM0.5和Zr-CaM1中氧化锆的负载率分别为3.71%、14.75%和26.01%。（3）实验发现，锆改性蒙脱石对低浓度磷酸盐具有强烈的吸附作用，且吸附效果随锆负载量的增加而增加，其吸附等温线数据更符合Langmuir模型，表明锆改性蒙脱石对水中磷酸盐的吸附机理属于单分子层的化学吸附。吸附动力学机制可以用准二级和Elovich模型进行很好地拟合。Zr-CaM1的最大吸附容量达22.41 mg/g，远高于Phoslock的9.49 mg/g。此外，Zr-CaM1吸附水体磷酸盐具有较宽的pH值适用范围（4～8.5），且酸性条件更佳。共存阴离子HCO3-会一定程度地抑制除磷效果，而Cl-和SO42-影响甚微。（4）污染沉积物钝化模拟实验显示，经投加锆改性蒙脱石15 d后，上覆水体磷浓度趋于稳定，保持在0.01 mg/L左右，孔隙水中SRP浓度快速降低。锆改性蒙脱石中锆、钙离子以配位离子交换形式与水体中的磷酸盐作用，并在沉积物-水界面以下形成薄层“钝化静止层”，从而有效固着和降低沉积物中可交换磷的二次释放。（5）综上研究表明，Zr-CaM1是一种高效、经济、安全的新型控磷材料，在水体和沉积物的磷污染修复中具有较为广阔的应用前景。

Eutrophication is a worldwide pollution problem of water environment. Phosphorus is considered as the key limiting factor of water eutrophication. Its excessive input poses a serious harm to aquatic ecosystem and human health. Therefore, how to effectively reduce the concentration of phosphate in eutrophic water has become a hot issue in the research field of water pollution. Even if the exogenous phosphorus in freshwater lakes and reservoirs is effectively curbed, sedimentary phosphorus will be released under specific environmental condition and maintain the eutrophication status for a long time. Therefore, controlling of phosphorus loading in polluted waterbody and sediment is an important part of eutrophication control.Adsorption and in-situ passivation are two main remediation techniques of phosphorus pollution in eutrophic water and sediments. Montmorillonite is a kind of inorganic ultra-high molecular weight silicate polymer with natural nano-characteristics. It has been widely applied in the environmental pollution control, because of large specific surface area, many pores strong surface adsorption and ion exchange. Zirconium oxide has stable physico-chemical properties, low water solubility, no toxicity and strong adsorption capacity for phosphate in waterbody. Hence, it is an innovative attempt to use zirconium modified montmorillonite for the control of phosphorus pollution in surface water and sediments. In the present research, performance parameters of different types of montmorillonite from main producing areas were characterized, and the optimum montmorillonite was selected as the adsorbent matrix. Zirconium modified montmorillonite was prepared by surface cross-linking method, and further applied in the control of phosphorus in polluted water and sediment from freshwater lakes and reservoirs. The main results are as follows:(1) Calcium-based montmorillonite from Inner Mongolia has weak alkalinity, high purity, moderate interlayer spacing， high cation exchange capacity and a certain adsorption phosphorus capacity. It is suitable for preparation of modified adsorbent.(2) Zirconium modified calcium-based montmorillonite was synthetically characterized by XRD, SEM-EDS and XRF. Results show that zirconium is successfully loaded on the surface and interlayer domain of calcium-based montmorillonite, and part of montmorillonite interlayer structures are destroyed. The loading of zirconium increases with the increase of the proportion of zirconium source. The loading rates of zirconia in Zr-CaM0.1, Zr-CaM0.5 and Zr-CaM1 are 3.71%, 14.75% and 26.01%, respectively. (3) Zirconium modified montmorillonite strongly adsorbs low concentration phosphates in surface water. Adsorption effect increases with the increase of zirconium loading. The adsorption isotherm data are consistent with Langmuir model, indicating the chemical adsorption of single molecular layer. The adsorption kinetics can be well fitted by quasi-second-order and Elovich models. The maximum adsorption capacity of Zr-CaM1 22.41 mg/g is far higher than Phoslock 9.49 mg/g. Additionally, Zr-CaM1 had a wide pH range (4~8.5) for phosphate adsorption in water and favor for the acidic condition. The coexistence anion HCO3- inhibits phosphorus removal to a certain extent, whereas Cl- and SO42- have little impact.(4) Simulated passivation experiment of contaminated sediments shows that the phosphorus concentration in the overlying water remain 0.01 mg/L after 15 days of adding zirconium modified montmorillonite, while the SRP concentration in pore water decreases rapidly. Zirconium and calcium ions in zirconium modified montmorillonite can interacted with phosphates in water by coordination ion exchange, and form a thin "passive static layer" to effectively fix and reduce phosphorus release from sediment.(5) In conclusion, Zr-CaM1 is a new phosphorus control material with high efficiency, economy and safety. It may have a wide application in pollution remediation of surface water and sediment.