MW-Fe^0_H2O2体系预处理垃圾渗滤液浓缩液有机物

中国环境科学2018,38(6)：2144~2156ChinaEnvironmentalScienceMW-Fe0/H2O2体系预处理垃圾渗滤液浓缩液有机物张爱平1*,陈炜鸣2,李启彬2,蒋国斌2,辜哲培1(1.四川师范大学化学与材料科学学院,四川成都610068；2.西南交通大学地球科学与环境工程学院,四川成都611756)摘要：为探究MW-Fe0/H2O2类芬顿反应对渗滤液浓缩液的效能与机理,探讨了废水初始pH值、Fe0投加量、H2O2投加量、MW功率和反应时间等影响因素对有机物去除效果,通过类比实验对MW-Fe0/H2O2体系处理渗滤液浓缩液中MW辐射的反应机理进行研究,并采用了SEM和XRD技术对反应前后的Fe0物相变化及催化机理进行了探究.结果表明,在初始pH值为3.0,Fe0投加量0.5g/L,H2O2投加量20mL/L,MW功率400W,反应时间14min时,其COD、UV254以及色度(CN)的去除率分别为58.70%、85.69%和88.30%.类芬顿类比实验说明MW-Fe0/H2O2体系处理后具有较高的有机物去除率和可生化性;紫外-可见光谱表明,Fenton和MW-Fe0/H2O2类芬顿反应均能使废水中有机物的芳香性程度、分子量和缩合度大幅度降低,但MW-Fe0/H2O2类芬顿反应优于其他反应过程;三维荧光光谱显示,MW-Fe0/H2O2类芬顿反应能使渗滤液浓缩液中荧光峰峰位蓝移,说明废水的腐殖质缩合度减小,且分子量大幅降低.与此同时,Fe0在反应过程中,表面由光滑变得粗糙且被腐蚀为Fe3O4和FeOOH等物质.MW-Fe0/H2O2类芬顿反应的主要机理为芬顿反应及铁氧化物-H2O2非均相芬顿反应的高级氧化作用、铁基胶体对有机物的吸附沉淀,而MW的热效应和非热效应加速了以上作用的进行,从而能对渗滤液浓缩液中有机污染物进行快速去除.关键词：渗滤液浓缩液；Fe0/H2O2；MW；有机物中图分类号：X703文献标识码：A文章编号：1000-6923(2018)06-2144-13EnhanceddegradationofrefractoryorganicsinleachateconcentratesbyFe0/H2O2coupledwithmicrowaveirradiation.ZHANGAi-ping1*,CHENWei-ming2,LIQi-bin2,JIANGGuo-bin2,GUZhe-pei1(1.ChemistryandMaterialScienceofSichuanNormalUniversity,Chengdu610068；2.GeosciencesandEnvironmentalEngineeringofSouthwestJiaotongUniversity,Chengdu611765),ChinaEnvironmentalSicence,2018,38(6)：2144~2156Abstract：TostudytheeffectandmechanismofMW-Fe0/H2O2Fenton-likeprocessonconcentratedleachate,theeffectsofinitialpH,Fe0dosage,H2O2dosage,MWpowerandreactiontimeontheremovaloforganicsubstanceswereinvestigated.ThephasechangeofFe0beforeandafterreactionanditscatalyticmechanismwereinvestigatedbySEMmicrographandXRDspectra.ResultsshowedthattheremovalefficienciesofCOD,UV254andCNwere58.70%,85.69%and88.30%atinitialpHof3.0,Fe0dosageof0.5g/L,H2O2dosageof20mL/L,MWpowerof400Wandreactiontimeof14min.ComparisonofdifferentFenton-likeprocessindicatedthatahigherremovalefficiencyoforganicsubstancesandagreaterbiodegradabilitywereachievedafterMW-Fe0/H2O2Fenton-likeprocess.UV-VisspectraillustratedthatbothFentonandMW-Fe0/H2O2processescansignificantlydecreasethearomaticitydegree,molecularwei