单宁酸-钛复合吸附剂的制备及其对氟喹诺酮类抗生素的吸附去除  

Preparation of tannic acid-titanium composite adsorbent and its adsorption performance and mechanisms in removal of fluoroquinolone antibiotics

作　　者：常慊慊 高博强 刘波[1,2] 龙超[1,2] 杨琥[1,2] CHANG Qianqian;GAO Boqiang;LIU Bo;LONG Chao;YANG Hu(State Key Laboratory of Pollution Control and Resource Reuse,School of the Environment,Nanjing University,Nanjing,210023,China;Quanzhou Institute for Environmental Protection Industry,Nanjing University,Quanzhou,362000,China)

机构地区：[1]南京大学环境学院,污染控制与资源化研究国家重点实验室,南京210023 [2]泉州南京大学环保产业技术研究院,泉州362000

出　　处：《环境化学》2022年第7期2180-2192,共13页Environmental Chemistry

基　　金：国家自然科学基金(42061144014);泉州市科技计划(2021CT001)资助

摘　　要：本文以一种绿色环保且来源广泛的天然高分子单宁酸(TA)为原材料,四氯化钛为改性剂,一步法制得一系列单宁酸-钛(TA-Ti)复合吸附剂.首先通过多种表征技术考察了吸附剂的分子结构及其表面微观形貌等;针对目前在地表水中已发现的氟喹诺酮类抗生素(FQs),以氧氟沙星(OFL)为代表,系统研究了TA-Ti对OFL的吸附性能,详细考察了溶液pH、污染物浓度、吸附时间及不同共存物等对TA-Ti吸附性能的影响;并对具有与OFL相似结构的FQs及其两种亚结构类似物的吸附效果进行对比,结合吸附前后吸附剂傅里叶红外光谱和X射线光电子能谱谱图的变化,以及吸附动力学与等温吸附模型分析等,深入探讨了TA-Ti对OFL的吸附机制.TA可通过静电吸引、氢键、负电荷辅助氢键及π—π相互作用等与FQs作用;此外,钛离子不仅作为TA的交联剂,同时还可通过螯合作用协同吸附FQs,有效提高TA对FQs的吸附性能,对OFL理论最优吸附量为1.028 mmol·g^(−1).本文提供了一种绿色环保的高效吸附剂材料,可有效地净化FQs有机微污染水体,提高用水安全.In this work,a series of novel composite adsorbents(TA-Ti)was fabricated using tannic acid(TA)as the raw material and titanium tetrachloride as the modifier.TA is a commonly natural polymer with the advantages of wide source and environmental-friendliness.The molecular structure and surface morphology of this composite adsorbent were investigated by various characterizations.Fluoroquinolones antibiotics(FQs)were currently found in surface water.Among various FQs,ofloxacin(OFL)was selected as a representative in this work.The adsorption performance of TA-Ti in removal of OFL has been investigated systematically.The effects of solution pH,OFL concentration,contact time,coexisting inorganic salt and natural organic substance were studied in detail.The behaviors of TA-Ti in adsorption of some FQs with similar structures to OFL and their two substructural analogies were compared.The adsorption mechanisms have been discussed in detail on the basis of the changes in the Fourier transform infrared and X-ray photoelectron spectra of TA-Ti before and after adsorption as well as the analysis of the adsorption kinetics and isotherms.The efficient adsorption of FQs by TA-Ti was ascribed to the synergetic effects of electrostatic attraction,hydrogen bonding,negatively charged assisted hydrogen bonding,and π—πinteractions between TA and FQs;besides,Ti^(4+) not only acted as a cross-linking agent for TA but also synergistically adsorbed FQs through chelation effect,thereby causing a notably improved adsorption performance.The theoretical maximal OFL uptake of TA-Ti was 1.028 mmol·g^(−1).In short,this work provided an environmentally-friendly and high-efficient adsorbent that can effectively purify organic micro-polluted water and further improve water safety.

关 键 词：氟喹诺酮类抗生素 氧氟沙星 单宁酸 钛离子 吸附性能 吸附机制 

分 类 号：TQ424[化学工程] X703[环境科学与工程—环境工程]