epa-method-3005a

CD-ROM3005A-1Revision1July1992METHOD3005AACIDDIGESTIONOFWATERSFORTOTALRECOVERABLEORDISSOLVEDMETALSFORANALYSISBYFLAAORICPSPECTROSCOPY1.0SCOPEANDAPPLICATION1.1Method3005isanaciddigestionprocedureusedtopreparesurfaceandgroundwatersamplesforanalysisbyflameatomicabsorptionspectroscopy(FLAA)orbyinductivelycoupledargonplasmaspectroscopy(ICP).SamplespreparedbyMethod3005maybeanalyzedbyAASorICPforthefollowingmetals:AluminumMagnesiumAntimony**ManganeseArsenic*MolybdenumBariumNickelBerylliumPotassiumCadmiumSelenium*CalciumSilverChromiumSodiumCobaltThalliumCopperVanadiumIronZincLead*ICPonly**MaybeanalyzedbyICP,FLAA,orGFAA1.2Whenanalyzingfortotaldissolvedmetalsfilterthesample,atthetimeofcollection,priortoacidificationwithnitricacid.2.0SUMMARYOFMETHOD2.1Totalrecoverablemetals-Theentiresampleisacidifiedatthetimeofcollectionwithnitricacid.Atthetimeofanalysisthesampleisheatedwithacidandsubstantiallyreducedinvolume.Thedigestateisfilteredanddilutedtovolume,andisthenreadyforanalysis.2.2Dissolvedmetals-Thesampleisfilteredthrougha0.45-µmfilteratthetimeofcollectionandtheliquidphaseisthenacidifiedatthetimeofcollectionwithnitricacid.Samplesfordissolvedmetalsdonotneedtobedigestedaslongastheacidconcentrationshavebeenadjustedtothesameconcentrationasinthestandards.3.0INTERFERENCES3.1Theanalystshouldbecautionedthatthisdigestionproceduremaynotbesufficientlyvigoroustodestroysomemetalcomplexes.CD-ROM3005A-2Revision1July1992Precipitationwillcausealoweringofthesilverconcentrationandthereforeaninaccurateanalysis.4.0APPARATUSANDMATERIALS4.1Griffinbeakersofassortedsizesorequivalent.4.2Watchglassesorequivalent.4.3Qualitativefilterpaperandfilterfunnels.4.4Graduatedcylinderorequivalent.4.5Electrichotplateorequivalent-adjustableandcapableofmaintainingatemperatureof90-95C.o5.0REAGENTS5.1Reagentgradechemicalsshallbeusedinalltests.Unlessotherwiseindicated,itisintendedthatallreagentsshallconformtothespecificationsoftheCommitteeonAnalyticalReagentsoftheAmericanChemicalSociety,wheresuchspecificationsareavailable.Othergradesmaybeused,provideditisfirstascertainedthatthereagentisofsufficientlyhighpuritytopermititsusewithoutlesseningtheaccuracyofthedetermination.5.2ReagentWater.Reagentwatershallbeinterferencefree.Allreferencestowaterinthemethodrefertoreagentwaterunlessotherwisespecified.RefertoChapterOneforadefinitionofreagentwater.5.3Nitricacid(concentrated),HNO.Acidshouldbeanalyzedto3determinelevelofimpurities.IfmethodblankisMDL,thenacidcanbeused.5.4Hydrochloricacid(concentrated),HCl.Acidshouldbeanalyzedtodeterminelevelofimpurities.IfmethodblankisMDL,thenacidcanbeused.6.0SAMPLECOLLECTION,PRESERVATION,ANDHANDLING6.1AllsamplesmusthavebeencollectedusingasamplingplanthataddressestheconsiderationsdiscussedinChapterNineofthismanual.6.2Allsamplecontainersmustbeprewashedwithdetergents,acids,andwater.Bothplasticandglasscontainersaresuitable.6.3Sampling6.3.1Totalrecoverablemetals-AllsamplesmustbeacidifiedatthetimeofcollectionwithHNO(5mL/L).36.3.2Dissolvedmetals-Allsamplesmustbefilteredthrougha0.45-µmfilterandthenacidifiedatthetimeofcollectionwithHNO3(5mL/L).CD-ROM3005A-3Revision1July19927.0PROCEDURE7.1Transfera100-mLaliquotofwell-mixedsampletoabeaker.7.2Formetalsthataretobeanalyzed,add2mLofconcentratedHNOand35mLofconcentratedHCl.Thesampleiscoveredwitharibbedwatchglassorothersuitablecoversandheatedonasteambath,hotplateorotherheatingsourceat90to95Cuntilthevolumehasbeenreducedto15-20mL.oCAUTION:Donotboil.Antimonyiseasilylostbyvolatilizationfromhydrochloricacidmedia.7.3Removethebeakerandallowtocool.Washdownthebeakerwallsandwatchglasswithwaterand,whennecessary,filterorcentrifugethesampletoremovesilicatesandotherinsolublematerialthatcouldclogthenebulizer.Filtrationshouldbedoneonlyifthereisconcernthatinsolublematerialsmayclogthenebulizer;thisadditionalstepisliabletocausesamplecontaminationunlessthefilterandfilteringapparatusarethoroughlycleanedandprerinsedwithdiluteHNO.37.4Adjustthefinalvolumeto100mLwithreagentwater.8.0QUALITYCONTROL8.1AllqualitycontrolmeasuresdescribedinChapterOneshouldbefollowed.8.2Foreachanalyticalbatchofsamplesprocessed,blanksshouldbecarriedthroughouttheentiresamplepreparationandanalyticalprocess.Theseblankswillbeusefulindeterminingifsamplesarebeingcontaminated.RefertoChapterOnefortheproperprotocolwhenanalyzingblanks.8.3Replicatesamplesshouldbeprocessedonaroutinebasis.Areplicatesampleisasamplebroughtthroughthewholesamplepreparationandanalyticalprocess.Replicatesampleswillbeusedtodetermineprecision.Thesampleloadwilldictatethefrequency,but5%isrecommended.RefertoChapterOnefortheproperprotocolwhenanalyzingreplicates.8.4Spikedsamplesorstandardreferencematerialsshouldbeemployedtodetermineaccuracy.Aspikedsampleshouldbeincludedwitheachbatch.RefertoChapterOnefortheproperprotocolwhenanalyzingspikes.9.0METHODPERFORMANCE9.1Nodataprovided.CD-ROM3005A-4Revision1July199210.0REFERENCES1.Rohrbough,W.G.;etal.ReagentChemicals,AmericanChemicalSocietySpecifications,7thed.;AmericanChemicalSociety:Washington,DC,1986.2.1985AnnualBookofASTMStandards,Vol.11.01;StandardSpecific