重金属污染土壤原位钝化修复研究进展

*王立群1,2罗磊2,3**马义兵2韦东普2华珞1(1,100037;2,100081;3,100085)重金属原位钝化技术是一种污染土壤的修复方法,指向污染土壤添加一些活性物质(钝化修复剂),以降低重金属在土壤中的有效浓度或改变其氧化还原状态,从而有效降低其迁移性毒性及生物有效性.本文基于原位钝化修复剂种类研究方法评价指标作用机制以及风险评价等方面的研究,深入分析了该领域的研究现状和存在问题,并提出了今后研究的重点.目前广泛使用的钝化修复剂主要有粘土矿物磷酸盐有机堆肥及微生物材料等.由于土壤结构和组分的复杂性,钝化修复剂的作用机制尚不完全清楚,其可能的机制主要包括沉淀反应化学吸附与离子交换表面沉淀有机络合和氧化还原等.今后应加强从分子水平研究重金属的钝化机制,重点关注钝化修复重金属污染土壤时存在的潜在风险以及钝化修复的长期田间效应.重金属污染原位钝化修复土壤1001-9332(2009)05-1214-09X53AInsituimmobilizationremediationofheavymetals-contaminatedsoils:Areview1WANGL-iqun1,2,LUOLei2,3,MAY-ibing2,WEIDong-pu2,HUALuo1(1CapitalNormalUniversity,Beijing100037,China;2MinistryofAgricultureKeyLaboratoryofPlantNutritionandNutrientCycling,In-stituteofAgriculturalResourcesandRegionalPlanning,ChineseAcademyofAgriculturalSciences,Beijing100081,China;3StateKeyLaboratoryofEnvironmentalChemistryandEcotoxicology,Re-searchCenterforEco-EnvironmentalSciences,ChineseAcademyofSciences,Beijing100085,Chi-na).-Chin.J.Appl.Ecol.,2009,20(5):1214-1222.Abstract:Insituimmobilizationofheavymetalsincontaminatedsoilsbyaddingextraneousactiveamendmentshasbeenconsideredasacos-teffectivemeasureforcontaminatedsoilremediation.Ap-plicationofimmobilizationamendmentscandecreasetheavailablefractionsofheavymetalsorchangetheirredoxstates,andthus,effectivelydecreasethemobility,bioavailability,andtoxicityoftheheavymetalsinsoils.Thispapersummarizedthepresentresearchesabouttheinsituimmob-ilizationofheavymetalsinsoils,includingkindsofimmobilizationamendments,researchmethods,immobilizationindexes,immobilizationmechanisms,andrelevantenvironmentalriskassessmen.tThemostlyappliedamendmentsincludeclayminerals,phosphates,organiccomposts,andm-icrobes.Duetothecomplexityofsoilmatrixandthelimitationsofcurrentanalyticaltechniques,theexactimmobilizationmechanismshavenotbeenclarified,whichcouldincludeprecipitation,chem-icaladsorptionandionexchange,surfaceprecipitation,formationofstablecomplexeswithorganicligands,andredoxreaction.Theprospectsandlimitationsofinsituimmobilizationofheavymetalsinsoilswerediscussed.Futureworkshouldfocusontheelucidationofimmobilizationmechanismsatmolecularscale,withspecificattentionbepaidtothepotentialrisksofapplyingimmobilizationamendmentsanditslong-termeffectsonfieldsoils.Keywords:heavymeta;lcontamination;insituimmobilization;remediation;soi.l*(2006AA06Z360)(2006BAD17B04)(20070410100).**.E-mai:[e-mail]2008-11-03,2009-03-01.20095205ChineseJournalofAppliedEcology,May2009,20(5):1214-1222,.(AsCdHgPb)[1].,2000hm2,20%[2],[3].,,.,:1),;2),,,[4-6],.,,[6-8].,,[9-14].2000,,,.1,,-,,,(),[5,10-11]..111,.,:()()().,,[5]..pHPb,[15-16].,,CdPbZn[17],Jiao[18]Cd.,,As[10,19],As,[10,20].,[21].,()[22-23].Liu[24]CdCuZn,22250mg#kg-1.Lombi[21-22],.AsCr[25],,.,.(),,[16].Xu[26]Cr(+5),Cr;Liu[27]CuPb,CuPb,CuPb.Way-chunas[25],.112155:1Tab.1Types,amountapplied,objectiveelements,researchmethodsandimmobilizationefficiencyofinorganicamend-mentsforheavymetalimmobilizingremediationTypeofamendmentAmountapplied(%)HeavymetalMethodImmobilizationefficiencyA1~18Cd,Pb,ZnSolutetransportexperimentDe-creasingmetalelutedfromsoilviaimmob-ilization(77%)[28]CaCO3KH2PO4Ka-olinamorphousderivative1~2Cd,ZnSorptionexperiment,isotopicdilutiontech-niqueBC1Cd,Cu,Pb-Sorptionexper-iment,speciationanalysisEnhan-cingmetalretentioncapacityofsoil[30]Phosphatecompound0125,015Pb-Potexperiment,sequentialextractionprocedure(SEP),speciationanalysisEnhan-cingresidualfractionofPb,reducingplantuptake[15]Phosphatecompound0125,015PbDDecreasingthebioac-cessibilitytohuman[31]CaHPO4,CaCO30150~6125Cd,Cu,N,iPb,ZnSoilleaching87%Decrea-singextractablemetalfractioninsoilsmorethan87%[32]Phosphatecompound5Cu,Pb,ZnEFH3PO4,high-Feby-product,superphosphate110~312Cd,Pb,ZnInvitrochemicalextraction,plantexperimentinfield,feedingex-perimentwithanimals,Decreasingextractablemetalfractioninsoilsandmetalconcentrationsinplantandtissueofanimals[17]Hydroxyapatite014Cd,PbSorptionexperimentGSinglesuperphosphate,Ca-Mgphosphate,phosphaterock10PbSEPPb,PbDe-creasingsolublePbandformingleadpre-cipitation[35]Redmud,cyclonicashes,phosphate,lime1~5Cd,Pb,ZnChemicalsolution,plantsandsoilm-icrobiotaexperimentDe-creasingextractablefractionsandbiotoxicityofmetals[36]Redmud,flyash10As,Cd,CuPb,ZnSorptionexper-iment,leachingcolumnsSignificantlydecreasingmetalreleasefromeluate[37]Redmud,beringite0125~5100Cd,Cu,N,iZnPotexperiment,SEP,microbialexperimentIRedmud,zeolite,lime015~1010Cd,Pb,ZnSEP,microbialexperimentJIron(II)sulphate215,5AsSoilco-lumnleachingexperiments,SEPKFe,Aloxyhydrox-ides1,5AsSoilcolumnleachingexper-imentAs50%DecreasingAsineluate(50%)[20]Meerschaum1,2CdPotexperimentCd,CdDecreasingCduptakebyplantsandCdcontentinplants[38]Bonechar0102~1160Pb-Potexperiment,SEP,speciationa-nalysis,Enhan-cingtheresidualfractionofPbanddecrea-singplantuptake[39-40]Zeolite8Cu,Pb,Zn,Batchchemicalculture,ageingeffectanalysisEDTA,DecreasingEDTA-extractablefractionofmetalsinsoilswithstableandlastingeffects[8]Ca(OH)2Zeolite10,0105Cd,Pb,Zn-Potexperiment,SEP,speciationa-nalysis,Enhan-cingresidualfractionofmetalsinsoilanddecreasingplantuptake[41