二氧化钛滤柱对高砷污酸废水的吸附去除王文凯

113Vol．11No．320173ChineseJournalofEnvironmentalEngineeringMar．20172015CB9320032015－11－172016－01－081989—。[e-mail]*[e-mail]123123*1．7100552．1000853．100049。TiO2。3TiO22.5g·L－1＜0.5mg·L－1。EBCTEBCT=20minTiO2。TiO2H2SO4NaOH。XTiO2。Xμ-XＲF。KXμ-XANES。。pH。TiO2。TiO2X703.1A1673-9108201703-1322-07DOI10.12030/j．cjee．201511128Arseniteadsorptionremovalfromacidwastewaterusingtitaniumdioxidead-sorptionfiltercolumnWANGWenkai1YANLi23DUANJinming1JINGChuanyong23*1．SchoolofEnvironmentalandMunicipalEngineeringXi'anUniversityofArchitectureandTechnologyXi'an710055China2．ＲesearchCenterforEco-EnvironmentalSciencesChineseAcademyofSciencesBeijing100085China3．UniversityofChineseAcademyofSciencesBeijing100049ChinaAbstractＲemediationofmetallurgicalindustrywastewaterhaspresentedagreatenvironmentalchallengefordecades．InthisstudyaremediationtechniqueforAsⅢadsorptiveremovaladsorbentregenerationandAsⅢrecoverywasproposed．UsingthreegranularTiO2columnsinseriesAsIIIwithinitialconcentrationof2.5g·L－1couldbereducedtobelowthewastewaterdischargelimitof0.5mg·L－1．OptimizationoftheemptybedcontacttimeEBCTsuggestedthata20minEBCTwassufficientforAsⅢremoval．ThespentTiO2couldberegeneratedusingH2SO4andNaOH．TheX-raydiffractionpatternsofpristineandspentTiO2revealnochangeinthecrystallinestructurewhichensuresitshigheffectivenessafterregenerationandenablesitsreuse．Synchrotron-radiation-basedmicro-beamX-rayfluorescenceμ-XＲFwasusedtoanalyzetheinsituelementalcompositionofthesolidresidueafterregenerationrevealingthecoexistenceofmanyheavymetals．ArsenicK-edgemicro-focusX-rayabsorptionnear-edgestructureμ-XANESanalysissuggestedtheexistenceofAsⅤinthesolidresidueindicatingthatstrongalkaliconditionsduringtheregenerationprocessmayfacilitatetheoxida-tionofAsⅢ．Thesmallamountsofsolidresidueproducedduringtheadsorbentregenerationprocessmaybeusedasarawmaterialfortheproductionofarseniccompounds．ThewastesolutioncanbefurthertreatedaftermixingwithrawwatertoadjustthepHtoneutral．Thisadsorptionregenerationandreuseprocessprovidesan3innovativetechniqueformetallurgicalindustrywastewaterremediationthatispromisingforpracticalapplications．KeywordsarsenitemetallurgicalwastewatergranularTiO2columnadsorbentregeneration1-3。。、、、4-6。HDSpH7。8-10。、。、、、11-12。TiO2。TiO2。“”。1、1.12590±295mg·L－1。TiO2TiOSO4PVA13。300gTiOSO42L4℃5mol·L－1NaOHpH7.5100μS·cm－1。PVA3.3%10∶190℃40～600.25～0.42mmTiO2。TiO21a、b5nm。BETTiO2196m2·g－11c。XＲDTiO21d。1.22。TiO2。TiO2316cm1.2cm20gTiO2。0.45μm。31TiO2100mL。TiO2。2∶5pH。1.3EBCT10、2030min。AAS800PEICP-OES8000PE31。AASICP-OES0.7μg·L－14μg·L－1。HPLC-AFS0.6μg·L－11.7μg·L－1。3231111TiO2SEMa、TEMb、N2cXＲDdFig．1SEMaTEMbN2adsorptionanddesorptioncurvecandXＲDcharacterizationdofgranulesTiO22TiO2Fig．2SchematicflowchartforindustrialwastewatertreatmentprocessusingTiO2columnsTiO2100mL0.5mol·L－1H2SO42h5mol·L－1NaOH3TiO2。TiO20.5mol·L－1H2SO4TiO2。H2SO4NaOH70mL。TiO2。TiO2XXＲD。Xμ-XＲFKXμ-XANES。μ-XＲFμ-XANESBL15U1X。XSi11112keVXK-B4μm×4μm0.6mm×0.1mm1s4μmSDDVortexX。μ-XＲFIgorOriginPro8。μ-XANESK11867eV－150～300eV。Na2HAsO4·7H2ONaAsO2。IFEFFITμ-XANES。4231322.1EBCTEBCT3pH3。A、B、C3TiO2。。3EBCTaEBCT20minpHbFig．3EffluentAsⅢconcentrationsfromcolumnsinseriesasafunctionofbedvolumewithdifferentEBCTaandpHofeffluentinseriescolumnsasafunctionofbedvolumewhenEBCT=20minb1AEBCT102030minA115、131139mg·g－1TiO2。EBCT2030min10minEBCT2030minEBCT20minTiO2。20minEBCTTiO2EBCT14EBCT20min。10、2030minEBCT8.7、6.14.2μg·L－10.5mg·L－1。EBCT=20minpH6.6±0.56～9。2．24TiO2AsⅢFig．4AsⅢdesorptioncomparisonwithdifferentTiO2backwashingprocesses4。1、270mL0.5mol·L－1H2SO41～370mL5mol·L－1NaOH。OH－。375%90%TiO2。2．3。TiO2XＲD5。TiO2TiO25231115TiO2XＲDFig．5XＲDpatternsofTiO2beforeandafteradsorptionandregenerationTiO290.6%TiO2TiO2。2．4μ-XＲFKμ-XANESμ-XＲFμ-XANES15。μ-XＲF。μ-XＲFKμ-XANES6。μ-XＲF。μ-XANES25.2%74.8%。。。Eh=Eh0－0.059/npHH3AsO4aq+2H++2e－=H3AsO3aq+H2O116。6μ-XＲFKμ-XANESFig．6SpatialdistributionofAsbyXＲFmappingandAsK-edgeμ-XANESspectrasolidresidueXＲF7。XＲFTi、Ca、Fe、Zn、Ni、Pb、Cu、MnCr。。AsTiCa。X。AsAsTiCa。623137μ-XＲFFig．7Spatialdistributionofheavymetalelementsinsolidresiduebyμ-XＲFmappingwithdifferentfluorescenceintensityAsTi82Ｒ20.12012AsTiO2。μ-XＲFAsCaＲ20.7626AsCaCa。8AsTiCaFig．8CorrelationcurvebetweenAsandTiCainμ-XＲFmappingofsolidresidue2．5“”pH＞13。2∶5pH。“”。7231113TiO21TiO22“”3TiO2。1LUOTingCUIJinliHUShanetal．ArsenicremovalandrecoveryfromcoppersmeltingwastewaterusingTiO2J．Envi-ronmentalScience＆Technology201044239094-90982DUDKASADＲIANODC．EnvironmentalimpactsofmetaloreminingandprocessingAreviewJ．JournalofEnvironmen-talQuality1997263590-6023NOＲDSTＲOMDK．WorldwideoccurrencesofarsenicingroundwaterJ．Science200229655762143-21454MCDONALDDMWEBBJATAYLOＲJ．ChemicalstabilityofacidrockdrainagetreatmentsludgeandimplicationsforsludgemanagementJ．EnvironmentalScience＆Technology20064061984-19905WANGJWBEJANDBUNCENJ．ＲemovalofarsenicfromsyntheticacidminedrainagebyelectrochemicalpHadjustmentandcoprecipitationwithironhydroxideJ．EnvironmentalScience＆Technology200337194500-45066BASHACASELVISJＲAMASAMYEetal．ＲemovalofarsenicandsulphatefromthecoppersmeltingindustrialeffluentJ．ChemicalEngineeringJournal20081411/2/3