Designation:D4327−17StandardTestMethodforAnionsinWaterbySuppressedIonChromatography1ThisstandardisissuedunderthefixeddesignationD4327;thenumberimmediatelyfollowingthedesignationindicatestheyearoforiginaladoptionor,inthecaseofrevision,theyearoflastrevision.Anumberinparenthesesindicatestheyearoflastreapproval.Asuperscriptepsilon(´)indicatesaneditorialchangesincethelastrevisionorreapproval.1.Scope*1.1Thistestmethod2,3coversthesequentialdeterminationoffluoride,chloride,nitrite,ortho-phosphate,bromide,nitrate,andsulfateionsinwaterbysuppressedionchromatography.NOTE1—Orderofelutionisdependentuponthecolumnused;seeFig.1.1.2Thistestmethodisapplicabletodrinkingandwastewa-ters.Therangestestedforthistestmethodforeachanionwereasfollows(measuredinmg/L):Fluoride0.26to8.49Chloride0.78to26.0Nitrite-N0.36to12.0Bromide0.63to21.0Nitrate-N0.42to14.0o-Phosphate0.69to23.1Sulfate2.85to95.01.3Itistheuser’sresponsibilitytoensurethevalidityofthistestmethodforothermatrices.1.4Concentrationsaslowas0.01mg/Lweredetermineddependingupontheanionstobequantified,insinglelabora-torywork.Utilizinga50-µLsamplevolumeloopandasensitivityof3000µS/cmfullscale,theapproximatedetectionlimitsshowninTable1canbeachieved.Lowerdetectionlimitshavebeenobservedwithnewerinstrumentation,columntechnologyandeluents.Theanalystmustassureoptimuminstrumentperformancetomaintainastablebaselineatmoresensitiveconductivityfull-scalesettings.1.5Theupperlimitofthistestmethodisdependentupontotalanionconcentrationandmaybedeterminedexperimen-tallyasdescribedinAnnexA1.Theselimitsmaybeextendedbyappropriatedilutionorbyuseofasmallerinjectionvolume.1.6Usingalternateseparatorcolumnandeluentsmayper-mitadditionalanionssuchasacetate,formate,orcitratetobedetermined.Thisisnotthesubjectofthistestmethod.1.7Thistestmethodupdateapprovestheuseofelectrolyti-callygeneratedeluent,electrolyticallyregeneratedeluent,electrolyticsuppression(notautozeroing),andelectrolytictrapcolumnsalsoknownasreagent-freeionchromatography.Thisapprovalisbasedonacceptanc...
