氧化石墨烯改性污泥基生物炭对培氟沙星的去除机理研究  

Removal Mechanism of Pefloxacin by Graphene Oxide Modified Sludge Biochar

作　　者：郑永昕 魏东宁 余学 黄刘辉 胡辉美 黄红丽[1] ZHENG Yongxin;WEI Dongning;YU Xue;HUANG Liuhui;HU Huimei;HUANG Hongli(College of Resources and Environment,Hunan Agricultural University,Changsha 410128,China;Guangdong Jiabao City Management Technology Co.,Ltd.,Dongguan 523900,China)

机构地区：[1]湖南农业大学资源环境学院,湖南长沙410128 [2]广东家宝城市管理科技有限公司,广东东莞523900

出　　处：《环境科学研究》2020年第12期2879-2887,共9页Research of Environmental Sciences

基　　金：湖南省教育厅优秀青年项目(No.17B119);湖南省重点研究计划项目(No.2018SK2022)。

摘　　要：为获得培氟沙星废水高效去除的环境友好型吸附剂,以城市剩余污泥为原料制备了SBC(污泥基生物炭),并采用氧化石墨烯(GO)对其改性得到GO-SBC(氧化石墨烯改性生物炭),利用SEM和FTIR对其进行表征,通过静态吸附试验探讨了生物炭对培氟沙星的去除效果,并通过吸附模型和FTIR、XPS表征技术进一步探究了GO-SBC对培氟沙星的吸附机理.结果表明:①改性后的GO-SBC表面更加粗糙,生物炭表面含氧官能团数量增加.②动力学吸附研究表明,GO-SBC对培氟沙星的最大吸附容量为137.51 mg/g,比SBC对培氟沙星的吸附容量提高了40.32%,且GO-SBC对培氟沙星的吸附更符合伪二级动力学模型,表明吸附过程主要以化学吸附为主.③GO-SBC对培氟沙星的吸附符合Freundlich等温吸附模型,表明该吸附过程为多层吸附.④热力学研究表明,吸附过程为自发吸热反应.⑤GO-SBC对培氟沙星的吸附机制主要有两种作用,一种是π-π相互作用,另一种是GO-SBC的N-H与培氟沙星的C-H相互作用.研究显示,GO-SBC是一种高效去除培氟沙星的吸附剂,这为城市剩余污泥的资源化利用提供了出路,也为抗生素废水治理提供了方法.In order to obtain an environmentally friendly adsorbent for the efficient removal of pefloxacin in wastewater,SBC(sludge-based biochar)was prepared from urban surplus sludge and modified with graphene oxide to obtain GO-SBC(graphene oxide modified biochar).Their characterization was carried out through SEM and FTIR techniques.Furthermore,the removal efficiency of biochar before and after modification for pefloxacin was studied by adsorption experiments.Finally,the adsorption behavior of pefloxacin on GO-SBC was investigated through adsorption models,and the potential adsorption mechanisms were further studied by the FTIR and XPS techniques.The results showed that:(1)The GO-SBC surface became rougher,and there were more oxygen-containing functional groups compared with SBC.(2)The kinetics adsorption study showed that the removal rate of pefloxacin by GO-SBC increased by 40.32%compared with SBC,and its maximum adsorption capacity was 137.51 mg g;the adsorption process was in accordance with the pseudo-second-order kinetic model,indicating that the adsorption process was mainly chemical adsorption.(3)The adsorption of pefloxacin by GO-SBC conformed to the Freundlich model,indicating that the adsorption process was multi-layer adsorption.(4)Thermodynamic analysis showed that the adsorption process was a spontaneous endothermic reaction.(5)There were two main adsorption mechanisms of GO-SBC for pefloxacin.One was theπ-πinteraction,and the other was the interaction between N-H of GO-SBC and C-H on pefloxacin.Therefore,GO-SBC may be a highly effective adsorbent for removing pefloxacin,which provides the ideas for the resource utilization of urban residual sludge,and provides a method for antibiotic wastewater treatment.

关 键 词：氧化石墨烯 生物炭 培氟沙星 吸附机理 

分 类 号：X703[环境科学与工程—环境工程]