【作者】 王婷；

【导师】 王海鹰； 张安邦；

【作者基本信息】 中南大学 ， 工程（专业学位）， 2022， 硕士

【摘要】 工业含氟废水成分复杂、浓度高、酸度大,得到广泛关注。因操作简便、成本低,吸附法已经成为含氟废水的重要处理方法。然而,目前广泛应用的铝基等吸附材料在酸性溶液中不稳定、易溶出,难以有效应对工业含氟废水处理需求。本文基于化学氧化聚合法,探索了聚吡咯合成产物稳定性和吸附性能的因素影响,合成得到一类具有高稳定性聚吡咯（PPy）材料,实现了在酸性溶液环境中氟离子高效吸附分离;并通过铈原位负载,研究了聚吡咯材料铈掺杂强化对溶液除氟的影响规律,考察了其在实际酸性铅锌冶炼废水中应用情况,为工业含氟废水处置提供了一个可行技术方法。主要研究内容与结果如下:（1）合成得到具有良好酸稳定性和除氟性能的聚吡咯材料。基于化学氧化聚合法,研究了氧化剂种类、用量、腈水比等因素,对合成聚吡咯产物的结构及脱氟性能影响。并采用XRD、SEM和FTIR等表征手段,开展了聚吡咯产物的物相及形貌结构分析。最佳工艺条件为,在氧化剂与吡咯单体比例1.5:1,腈水比1:9,合成温度0℃,聚合时间5 h,得到的聚吡咯材料的稳定性最高。且相比文献报道的大多数相关材料和常用市售除氟树脂,合成产物展现了优异的除氟性能。在溶液p H≤3时,其吸附量在5-15 mg/g左右,明显优于已产业化的Purolite PFS951等树脂吸附性能（1-5 mg/g左右）。（2）考察了铈掺杂对聚吡咯复合材料的除氟行为及除氟性能,展现了在实际铅锌冶炼废水处理应用可行性。通过原位负载,引入高F^-亲和力的铈元素,制备得到一类HCe O₂@PPy复合材料,显著强化了聚吡咯溶液除氟性能,适用p H范围广（p H=1-11）,选择性好。研究发现,HCe O₂@PPy复合材料的氟吸附容量得到了显著提升（约为PPy的4倍）,其最大理论吸附容量为80.93 mg/g。在实际铅锌冶炼废水处理中,其对氟离子展现了较好的选择性吸附能力,去除率可达71.7%,展现了实际应用前景。（3）探究了HCe O₂@PPy对氟离子的强化吸附机理。研究发现,Ce-OH是高效的活性吸附F^-的结构,被吸附的氟离子与材料上的Ce-OH发生离子交换反应,形成化学键（Ce-F）从而被吸附去除。除氟机理包括（ⅰ）静电作用,HCe O₂@PPy通过静电作用将F^-吸附到表面;（ⅱ）离子交换作用,HCe O₂@PPy上的OH^-与F^-进行离子交换。图47幅,表17个,参考文献120篇更多还原

【Abstract】 Industrial fluorinated wastewater has attracted widespread attention due to its complex composition,high concentration and high acidity.However,common aluminum-based materials are unstable and easy to dissolve in acidic solution,which cannot effectively meet the needs of industrial fluorinated wastewater treatment.In this paper,the factors affecting the stability and adsorption performance of polypyrrole were explored based on the chemical oxidative polymerization method.A class of polypyrrole（PPy）materials with high stability was synthesized,which realized the efficient adsorption and separation of fluoride ions in an acidic solution environment.Through in-situ loading of cerium,the effect of cerium doping strengthening of polypyrrole material on the defluorination of solution was studied,and its application in the actual acid lead-zinc smelting wastewater was investigated,which provided a feasible technical method for the disposal of industrial fluorinated wastewater.The main research contents and results are as follows:（1）Polypyrrole materials with good acid stability and defluorination performance were synthesized.Based on the chemical oxidative polymerization method,the influence of factors such as the type of oxidant,the amount of oxidant,and the ratio of nitrile to water on the structure and defluorination performance of the synthesized polypyrrole was studied.The phase,morphology and structure of polypyrrole were analyzed by characterization of XRD,SEM and FTIR.The optimal process conditions are that the ratio of oxidant to pyrrole monomer is 1.5:1,the ratio of nitrile to water is 1:9,the synthesis temperature is 0℃,and the polymerization time is 5 h,and the obtained polypyrrole materials has the highest stability.Compared with most related materials reported in the literature and commonly used commercially available fluoride-removing resins,the synthesized product exhibits excellent fluoride-removing performance.When the solution p H≤3,the adsorption capacity is around 5-15 mg/g,which is significantly better than the industrialized Purolite PFS951 and other resin adsorption performance（around 1-5 mg/g）.（2）The fluoride removal behavior and performance of polypyrrole composites by cerium doping were investigated,that has demonstrated the feasibility of practical application in lead-zinc smelting wastewater treatment.Through in-situ loading high F^-affinity cerium element,a class of HCe O₂@PPy composites was prepared,which significantly enhanced the fluoride removal performance in solution.It is suitable for a wide p H range（p H=1-11）with good selectivity.Fluoride adsorption capacity of the HCe O₂@PPy composite was significantly improved（about 4 times that of PPy）,and its maximum theoretical adsorption capacity was 80.93 mg/g.In the actual treatment of lead-zinc smelting wastewater,it shows a good selective adsorption capacity for fluoride ions,and the removal rate can reach 71.7%,showing a practical application prospect.（3）The adsorption mechanism of fluoride ions on HCe O₂@PPy was explored.The study found that Ce-OH is an efficient and active structure for adsorbing F^-.Fluoride ions take ion exchange reaction with Ce-OH on the material to form a chemical bond（M-F）,which was adsorbed and removed.The mechanism of defluorination includes:（i）electrostatic interaction,in which HCe O₂@PPy adsorbs F^-to the surface through electrostatic interaction,（ii）ion exchange,in which OH^-on HCe O₂@PPy take ion exchange with F^-.This thesis contains 47 figures,17 tables and 120 references更多还原