改性纳米粘土结合堆肥材料对浅水湿地中重金属、农药和抗生素污染修复研究

The remediation of heavy metals, pesticides, antibiotics pollution are extremely important for protecting the ecological environment of shallow water wetlands. Due to the unique function and the complicated ecology of shallow water wetlands, the traditional pollution restoration method is difficult to achieve efficient, green and stable effectiveness. In this project, photocatalytic materials with visible light response were prepared by loading photocatalysts on nanoclays by techniques such as surface modification. Nanoclay/compost composites were prepared by using composting particles as the core and nanoclay-based photocatalysts as cladding materials in the presence of binder. The effects and mechanism of the composites on the adsorption and desorption of heavy metals, pesticides, antibiotics in shallow-water wetlands were studied. Moreover, the degradation efficiency and mechanism of pesticides and antibiotics under visible light were studied. Through continuous testing and feedback, composites with high adsorption capacity for heavy metals, pesticides, antibiotics, and high degradation efficiency of pesticides and antibiotics was selected. Through the environmental risk assessment, potting and field experiment of composite materials, the remedial agents, remediation techniques, methods and theories can be developed to be applied to the practical contaminated shallow water wetlands. The projectcan provide new ideas, new models and new technical approaches for the remediation of shallow water wetlands with high efficiency and low cost.

重金属、农药和抗生素污染的修复对于保护浅水湿地的生态环境具有重要意义。浅水湿地由于功能的独特性和生态的复杂性，传统的污染修复方式难以实现高效、绿色、稳定的修复效果。本项目通过表面修饰等技术在纳米粘土上负载光催化剂，制备具有可见光响应的光催化材料；以堆肥颗粒为核心，纳米粘土基光催化材料为裹覆材料，在粘结剂存在下制备纳米粘土-堆肥复合材料；研究复合材料对浅水湿地中重金属、农药、抗生素的吸附与解吸行为与机理及其在可见光下对农药与抗生素的降解效率和机理；通过不断地试验和反馈，筛选出同时对重金属、农药、抗生素的吸附能力强、对农药与抗生素的降解效率高的复合材料；通过对复合材料的环境风险评估、盆栽与实地试验等，形成能实际应用于受污染浅水湿地的修复剂及修复技术、方法和理论。本项目的研究成果可为浅水湿地的重金属、农药和抗生素污染的高效、低成本修复提供新思路、新模式和新技术。

重金属、农药和抗生素污染的修复对于保护浅水湿地生态环境具有重要意义。浅水湿地由于功能独特性和生态复杂性，传统污染修复方式难以实现高效、绿色、稳定的修复效果。本项目主要研究利用最新纳米技术对水滑石、蒙脱石、埃洛石等天然粘土矿物进行修饰改性，制备新型的改性粘土吸附材料和光催化材料，考察其协同堆肥材料修复土壤重金属污染和有机物污染的价值，并对其进入环境后的生态风险进行评估。.在项目实施期间，采用元素掺杂法、酸蚀刻法、高压水热法、共沉淀法等技术，合成了Mg(OH)2/MgO-蒙脱石、MgO-蒙脱石、MgFe2O4-蒙脱石、蒙脱石-镁铁水滑石、磁性碳-镁铁水滑石、羟基磷灰石-硅酸钙、硅酸镁水热碳、水铁矿-埃洛石等8种改性粘土吸附固化材料，它们对重金属吸附实验证实所制备吸附材料具有良好的吸附固化性能，尤其是蒙脱石-镁铁水滑石，对Pb(II)和Cd(II)的最大吸附性能分别可达1397.6和510.2 mg/g；土壤重金属污染修复的应用实验表明，所制备改性粘土吸附材料协同堆肥材料可有效固化土壤重金属，降低了土壤重金属的生物有效性，同时它们的环境风险较低。研究了改性纳米粘土对农药、抗生素的吸附作用；同时，研发了以改性水滑石为载体、负载掺杂氮化碳和铂酸秘的改性纳米粘土光催化剂，并考察了其对典型农药和抗生素的降解作用。本项目还合成了对农药抗生素具有潜在修复作用的一系列的光催化剂，研究了它们的合成方法、降解机理和应用潜力。对上述材料的环境风险评价表明这些改性粘土材料并不会对生态环境造成二次污染。.本项目所制备改性纳米粘土吸附材料协同堆肥材料的土壤重金属污染修复技术方法具有使用成本低、治理效率高和环境风险低的优势，所制备的改性纳米粘土光催化材料可直接利用太阳能降解有机污染物，为浅水湿地的重金属、农药和抗生素污染修复提供了新思路和新方法，具有良好应用前景。