【作者】 杨颖；

【导师】 赵迎新； 刘红磊；

【作者基本信息】 天津大学 ， 环境工程， 2019， 硕士

【摘要】 药品和个人护理品（PPCPs）是一类新兴微量污染物,其具有难生物降解性、生物蓄积性等特点,对动植物和人类身体健康造成极大威胁。吸附法具有简单、高效、便捷、可再生等优点,适用于水体中PPCPs污染物的去除。吸附剂决定了吸附过程的有效性。传统吸附剂存在效率低、二次污染等问题,开发一种低成本、高效率、环境友好的新型吸附剂材料意义重大。本研究利用导电聚合物对储量大、价格低的火山岩进行改性,制备出了聚吡咯负载火山岩复合型吸附剂材料。选择磺胺甲恶唑（SMX）为典型PPCPs污染物,深入分析其吸附过程和机理。本研究选择8种天然火山岩进行原料选优。利用化学氧化聚合法将聚吡咯负载到天然火山岩上,制备出聚吡咯负载火山岩复合材料,通过Minitab软件进行轴增强单纯质心设计,建立混料回归模型,根据SMX去除率和经济成本优化用量配比。通过批实验,对天然火山岩和聚吡咯负载火山岩去除SMX的吸附性能进行探讨（溶液初始pH值、溶液初始浓度、反应时间、吸附剂投加量、共存离子、脱附再生等）。通过SEM、EDX、FTIR、XRD、XPS等表征分析,结合吸附动力学、吸附等温线模型的拟合参数和吸附热力学参数分析,研究对SMX的吸附去除机理。研究结果表明,天然火山岩具有层状结构和较大的孔隙通道,主要矿物成分为无序透长石（Na,K）（Si₃Al）O₈。在p H为2时,得到最大的SMX去除率,投加量为20 g/L时,反应4 h达到吸附平衡。对SMX的吸附过程更符合Langmuir等温线模型和伪二级动力学模型,拟合最大吸附容量为0.33 mg/g。优化所得复合材料最佳质量配比为天然火山岩:吡咯:无水三氯化铁=0.10:0.28:0.62。聚吡咯负载火山岩表面粗糙,吡咯链交错衔接,形成团簇形态。相较天然火山岩,去除SMX适用的pH范围扩大至5～11,吸附平衡时间缩短至3 h。共存离子的影响大小为SO₄^2->NO₃^->PO₄^3->HCO₃^-。对SMX的吸附过程更符合Freundlich等温线模型和伪二级动力学模型,拟合所得最大吸附容量为4.2 mg/g,是天然火山岩的12.9倍。吸附热力学参数△H⁰值大于0,吸附反应为吸热过程。聚吡咯负载火山岩吸附SMX的机理主要为氢键作用、静电吸引和离子交换。该材料经过5次循环利用,对SMX去除率稳定,重复利用性能良好。综上所述,聚吡咯负载火山岩性能良好,在PPCPs污染物去除方面具有较好应用前景。更多还原

【Abstract】 Pharmaceuticals and personal care products（PPCPs）are a novel kind of emerging micro-pollutants,which are easily bioaccumulated but hardly biodegradable.The high detection rate of PPCPs poses a huge threat to the health of plants,animals and human beings.Due to the advantages of simplicity,high efficiency,convenience,regeneration,etc.,adsorption is used to remove PPCPs from water as a common methods.Studies to date have shown that the adsorbent determines the adsorption efficiency.However,traditional adsorbents have many disadvantages such as low removal efficiency and secondary pollution.It is of great significance to develop an novel environmental friendly adsorbent with low cost and high efficiency.In this study,the volcanic rock was modified by conductive polymer to prepare a polypyrrole-loaded volcanic composite adsorbent.Sulfamethoxazole（SMX）was selected as a typical PPCPs pollutant,its adsorption process and mechanism were analyzed in depth as well.In this study,eight natural volcanic rocks were selected for raw materials.Polypyrrole-loaded volcanic rock composites were prepared by the method of chemical oxidative polymerization.Minitab was used to carry out the axial enhancement simple centroid design,and a mixture regression model was established,while the dosage ratio was also optimized according to SMX removal rate and economic cost.The adsorption performance of that new adsorbent on SMX（initial p H,SMX concentration,adsorption time,adsorbent dosage,coexisting ions,adsorbent regeneration,etc.）was investigated by batch experiments.In addition,the adsorption mechanism of SMX was studied by various characterizations（SEM,EDX,FTIR,XRD,XPS）combined with adsorption kinetics,thermodynamics and isothermal adsorption.The results show that natural volcanic rocks are porous and stratified,with the main mineral composition:disordered feldspar（Na,K）（Si₃Al）O₈.Under the condition of p H=2,the maximum removal rate of SMX was obtained,and the adsorption reached equilibrium in 4 h with a dosage of 20 g/L.The adsorption process conforms to the Langmuir isotherm model and pseudo second-order kinetics.By fitting,the maximum adsorption capacity was 0.33 mg/g.The mass ratio of the adsorbent precursor was natural volcanic rock:pyrrole:Fe Cl₃=0.10:0.28:0.62,which was optimized by the mixture regression model.Due to the interlaced connection of pyrrole,the surface of the composite is rough and clustered.Compared with natural volcanic rocks,the p H for removing SMX was extended to 5～11,and the adsorption equilibrium time is shortened to 3 h.Coexisting ions have an effect on the adsorption of SMX:SO₄^2->NO₃^->PO₄^3->HCO₃^-.The adsorption process conforms to the Freundlich isotherm model and pseudo second-order kinetics.The maximum adsorption capacity was obtained by fitting was 4.2 mg/g,which is 12.9 times that of natural volcanic rocks.△H⁰>0 means that the adsorption process is endothermic.The adsorption mechanism of polypyrrole-loaded volcanic rocks on SMX is mainly hydrogen bonding,electrostatic attraction and ion exchange.Besides,the material still had stable removal efficiency after being recycled for 5 times,which showed a good reusability.In summary,polypyrrole-loaded volcanic rocks has significant performance in the removal of PPCPs,thus it has good application effect and promising development.更多还原