Designation:D7284−13StandardTestMethodforTotalCyanideinWaterbyMicroDistillationfollowedbyFlowInjectionAnalysiswithGasDiffusionSeparationandAmperometricDetection1ThisstandardisissuedunderthefixeddesignationD7284;thenumberimmediatelyfollowingthedesignationindicatestheyearoforiginaladoptionor,inthecaseofrevision,theyearoflastrevision.Anumberinparenthesesindicatestheyearoflastreapproval.Asuperscriptepsilon(´)indicatesaneditorialchangesincethelastrevisionorreapproval.1.Scope1.1Thistestmethodisusedtodeterminetheconcentrationoftotalcyanideinanaqueouswastewateroreffluent.Themethoddetectsthecyanidesthatarefree(HCNandCN-)andstrong-metal-cyanidecomplexesthatdissociateandreleasefreecyanidewhenrefluxedunderstronglyacidicconditions.1.2Thismethodmaynotbeapplicabletoprocesssolutionsfrompreciousmetalsminingoperations.1.3Thisprocedureisapplicableoverarangeofapproxi-mately2to500µg/L(partsperbillion)totalcyanide.Higherconcentrationscanbemeasuredwithsampledilutionorlowerinjectionvolume.1.4ThedeterminativestepofthismethodutilizesflowinjectionwithamperometricdetectionbasedonTestMethodD6888.Priortoanalysis,samplesmustbedistilledwithamicro-distillationapparatusdescribedinthistestmethodorwithasuitablecyanidedistillationapparatusspecifiedinTestMethodsD2036.1.5ThevaluesstatedinSIunitsaretoberegardedasstandard.Nootherunitsofmeasurementareincludedinthisstandard.1.6Thisstandarddoesnotpurporttoaddressallofthesafetyconcerns,ifany,associatedwithitsuse.Itistheresponsibilityoftheuserofthisstandardtoestablishappro-priatesafetyandhealthpracticesanddeterminetheapplica-bilityofregulatorylimitationspriortouse.Specifichazardstatementsaregivenin8.6andSection9.2.ReferencedDocuments2.1ASTMStandards:2D1129TerminologyRelatingtoWaterD1193SpecificationforReagentWaterD2036TestMethodsforCyanidesinWaterD2777PracticeforDeterminationofPrecisionandBiasofApplicableTestMethodsofCommitteeD19onWaterD3856GuideforManagementSystemsinLaboratoriesEngagedinAnalysisofWaterD5847PracticeforWritingQualityControlSpecificationsfo...
