ISO13320-2009 粒度分析-激光衍射法

ReferencenumberISO13320:2009(E)©ISO2009INTERNATIONALSTANDARDISO13320Firstedition2009-10-01Particlesizeanalysis—LaserdiffractionmethodsAnalysegranulométrique—MéthodespardiffractionlaserISO13320:2009(E)PDFdisclaimerThisPDFfilemaycontainembeddedtypefaces.InaccordancewithAdobe'slicensingpolicy,thisfilemaybeprintedorviewedbutshallnotbeeditedunlessthetypefaceswhichareembeddedarelicensedtoandinstalledonthecomputerperformingtheediting.Indownloadingthisfile,partiesacceptthereintheresponsibilityofnotinfringingAdobe'slicensingpolicy.TheISOCentralSecretariatacceptsnoliabilityinthisarea.AdobeisatrademarkofAdobeSystemsIncorporated.DetailsofthesoftwareproductsusedtocreatethisPDFfilecanbefoundintheGeneralInforelativetothefile;thePDF-creationparameterswereoptimizedforprinting.EverycarehasbeentakentoensurethatthefileissuitableforusebyISOmemberbodies.Intheunlikelyeventthataproblemrelatingtoitisfound,pleaseinformtheCentralSecretariatattheaddressgivenbelow.COPYRIGHTPROTECTEDDOCUMENT©ISO2009Allrightsreserved.Unlessotherwisespecified,nopartofthispublicationmaybereproducedorutilizedinanyformorbyanymeans,electronicormechanical,includingphotocopyingandmicrofilm,withoutpermissioninwritingfromeitherISOattheaddressbeloworISO'smemberbodyinthecountryoftherequester.ISOcopyrightofficeCasepostale56•CH-1211Geneva20Tel.+41227490111Fax+41227490947E-mailcopyright@iso.orgWebwww.iso.orgPublishedinSwitzerlandii©ISO2009–AllrightsreservedISO13320:2009(E)©ISO2009–AllrightsreservediiiContentsPageForeword............................................................................................................................................................ivIntroduction........................................................................................................................................................v1Scope.....................................................................................................................................................12Normativereferences...........................................................................................................................13Terms,definitionsandsymbols..........................................................................................................13.1Termsanddefinitions...........................................................................................................................13.2Symbols.................................................................................................................................................54Principle.................................................................................................................................................65Laserdiffractioninstrument................................................................................................................66Operationalprocedures.....................................................................................................................106.1Requirements......................................................................................................................................106.2Sampleinspection,preparation,dispersionandconcentration...................................................106.3Measurement.......................................................................................................................................126.4Precision..............................................................................................................................................146.5Accuracy..............................................................................................................................................156.6Errorsourcesanddiagnosis.............................................................................................................176.7Resolutionandsensitivity.................................................................................................................197Reportingofresults............................................................................................................................20AnnexA(informative)Theoreticalbackgroundoflaserdiffraction............................................................22AnnexB(informative)Recommendationsforinstrumentspecifications..................................................39AnnexC(informative)Dispersionliquidsforthelaserdiffractionmethod...............................................42AnnexD(informative)Refractiveindex,nm,forvariousliquidsandsolids..............................................43AnnexE(informative)Recommendationstoreachoptimumprecisionintestmethods.........................48Bibliography.....................................................................................................................................................50ISO13320:2009(E)iv©ISO2009–AllrightsreservedForewordISO(theInternationalOrganizationforStandardization)isaworldwidefederationofnationalstandardsbodies(ISOmemberbodies).TheworkofpreparingInternationalStandardsisnormallycarriedoutthroughISOtechnicalcommittees.Eachmemberbodyinterestedinasubjectforwhichatechnicalcommitteehasbeenestablishedhastherighttoberepresentedonthatcommittee.Internationalorganizations,governmentalandnon-governmental,inliaisonwithISO,alsotakepartinthework.ISOcollaboratescloselywiththeInternationalElectrotechnicalCommission(IEC)onallmattersofelectrotechnicalstandardization.InternationalStandardsaredraftedinaccordancewiththerulesgivenintheISO/IECDirectives,Part2.ThemaintaskoftechnicalcommitteesistoprepareInternationalStandards.DraftInternationalStandardsadoptedbythetechnicalcommitteesarecirculatedtothememberbodiesforvoting.PublicationasanInternationalStandardrequiresapprovalbyatleast75%ofthememberbodiescastingavote.Attentionisdrawntothepossibilitythatsomeoftheelementsofthisdocumentmaybethesubjectofpatentrights.ISOshallnotbeheldresponsibleforidentifyinganyorallsuchpatentrights.ISO13320waspreparedbyTechnicalCommitteeISO/TC24,Particlecharacterizationincludingsieving,SubcommitteeSC4,Particlecharacterization.ThisfirsteditionofISO13320cancelsandreplacesISO13320-1:1999.ISO13320:2009(E)©ISO2009–AllrightsreservedvIntroductionThelaserdiffractiontechniquehasevolvedsuchthatitisnowadominantmethodfordeterminationofparticlesizedistributions(PSDs).Thesuccessofthetechniqueisbasedonthefactthatitcanbeappliedtovariouskindsofparticulatesystems,isfastandcanbeautomated,andthatavarietyofcommercialinstrumentsisavailable.Nevertheless,theproperuseoftheinstrumentandtheinterpretationoftheresultsrequirethenecessarycaution.SincethepublicationofISO13320-1:1999,theunderstandingoflightscatteringbydifferentmaterialsandthedesignofinstrumentshaveadvancedconsiderably.Thisisespeciallymarkedintheabilitytomeasureveryfineparticles.Therefore,thisInternationalStandardhasbeenpreparedtoincorporatethemostrecentadvancesinunderstanding.INTERNATIONALSTANDARDISO13320:2009(E)©ISO2009–Allrightsreserved1Particlesizeanalysis—Laserdiffractionmethods1ScopeThisInternationalStandardprovidesguidanceoninstrumentqualificationandsizedistributionmeasurementofparticlesinmanytwo-phasesystems(e.g.powders,sprays,aerosols,suspensions,emulsionsandgasbubblesinliquids)throughtheanalysisoftheirlight-scatteringproperties.Itdoesnotaddressthespecificrequirementsofparticlesizemeasurementofspecificmaterials.ThisInternationalStandardisapplicabletoparticlesizesrangingfromapproximately0,1µmto3mm.Withspecialinstrumentationandconditions,theapplicablesizerangecanbeextendedabove3mmandbelow0,1µm.Fornon-sphericalparticles,asizedistributionisreported,wherethepredictedscatteringpatternforthevolumetricsumofsphericalparticlesmatchesthemeasuredscatteringpattern.Thisisbecausethetechniqueassumesasphericalparticleshapeinitsopticalmodel.Theresultingparticlesizedistributionisdifferentfromthatobtainedbymethodsbasedonotherphysicalprinciples(e.g.sedimentation,sieving).2NormativereferencesThefollowingreferenceddocumentsareindispensablefortheapplicationofthisdocument.Fordatedreferences,onlytheeditioncitedapplies.Forundatedreferences,thelatesteditionofthereferenceddocument(includinganyamendments)applies.ISO9276-1,Representationofresultsofparticlesizeanalysis—Part1:GraphicalrepresentationISO9276-2,Representationofresultsofparticlesizeanalysis—Part2:Calculationofaverageparticlesizes/diametersandmomentsfromparticlesizedistributionsISO9276-4,Representationofresultsofparticlesizeanalysis—Part4:CharacterizationofaclassificationprocessISO14488,Particulatematerials—SamplingandsamplesplittingforthedeterminationofparticulatepropertiesISO14887,Samplepreparation—Dispersingproceduresforpowdersinliquids3Terms,definitionsandsymbols3.1Termsanddefinitions3.1.1absorptionreductionofintensityofalightbeamnotduetoscatteringISO13320:2009(E)2©ISO2009–Allrightsreserved3.1.2coefficientofvariationCVrelativestandarddeviation(deprecated)⟨positiverandomvariable⟩standarddeviationdividedbythemeanNOTE1Thecoefficientofvariationiscommonlyreportedasapercentage.NOTE2AdaptedfromISO3534-1:2006[24],2.38.3.1.3complexrefractiveindexnprefractiveindexofaparticle,consistingofarealandanimaginary(absorption)partNOTEThecomplexrefractiveindexofaparticlecanbeexpressedmathematicallyasnp=np−ikpwhereiisthesquarerootof−1;kpisthepositiveimaginary(absorption)partoftherefractiveindexofaparticle;npisthepositiverealpartoftherefractiveindexofaparticle.IncontrasttoISO80000-7:2008[27],item7-5,thisInternationalStandardfollowstheconventionofaddingaminussigntotheimaginarypartoftherefractiveindex.3.1.4relativerefractiveindexmrelratioofthecomplexrefractiveindexofaparticletotherealpartofthedispersionmediumNOTE1AdaptedfromISO24235:2007[26].NOTE2Inmostapplications,themediumistransparentand,thus,itsrefractiveindexhasanegligibleimaginarypart.NOTE3Therelativerefractiveindexcanbeexpressedmathematicallyasmrel=np/nmwherenmistherealpartoftherefractiveindexofthemedium;npisthecomplexrefractiveindexofaparticle.3.1.5deconvolution⟨particlesizeanalysis⟩mathematicalprocedurewherebythesizedistributionofanensembleofparticlesisinferredfrommeasurementsoftheirscatteringpatternISO13320:2009(E)©ISO2009–Allrightsreserved33.1.6diffraction⟨particlesizeanalysis⟩scatteringoflightaroundthecontourofaparticle,observedatasubstantialdistance(inthe‘farfield’)3.1.7extinction⟨particlesizeanalysis⟩attenuationofalightbeamtraversingamediumthroughabsorptionandscattering3.1.8modelmatrixmatrixcontainingvectorsofthescatteredlightsignalsforunitvolumesofdifferentsizeclasses,scaledtothedetector'sgeometry,asderivedfrommodelcomputation3.1.9multiplescatteringconsecutivescatteringoflightbymorethanoneparticle,causingascatteringpatternthatisnolongerthesumofthepatternsfromallindividualparticlesNOTESeesinglescattering(3.1.20).3.1.10obscurationopticalconcentrationfractionofincidentlightthatisattenuatedduetoextinction(scatteringand/orabsorption)byparticlesNOTE1AdaptedfromISO8130-14:2004[25],2.21.NOTE2Obscurationcanbeexpressedasapercentage.NOTE3Whenexpressedasfractions,obscurationplustransmission(3.1.22)equalunity.3.1.11opticalmodeltheoreticalmodelusedforcomputingthemodelmatrixforopticallyhomogeneousandisotropicsphereswith,ifnecessary,aspecifiedcomplexrefractiveindexEXAMPLESFraunhoferdiffractionmodel,Miescatteringmodel.3.1.12reflection⟨particlesizeanalysis⟩changeofdirectionofalightwaveatasurfacewithoutachangeinwavelengthorfrequency3.1.13refractionprocessbywhichthedirectionofaradiationischangedasaresultofchangesinitsvelocityofpropagationinpassingthroughanopticallynon-homogeneousmedium,orincrossingasurfaceseparatingdifferentmedia[IEC60050-845:1987[28]]NOTETheprocessoccursinaccordancewithSnell'slaw:nmsinθm=npsinθpSee3.2forsymboldefinitions.ISO13320:2009(E)4©ISO2009–Allrightsreserved3.1.14repeatability(instrument)⟨particlesizeanalysis⟩closenessofagreementbetweenmultiplemeasurementresultsofagivenpropertyinthesamedispersedsamplealiquot,executedbythesameoperatorinthesameinstrumentunderidenticalconditionswithinashortperiodoftimeNOTEThistypeofrepeatabilitydoesnotincludevariabilityduetosamplinganddispersion.3.1.15repeatability(method)⟨particlesizeanalysis⟩closenessofagreementbetweenmultiplemeasurementresultsofagivenpropertyindifferentaliquotsofasample,executedbythesameoperatorinthesameinstrumentunderidenticalconditionswithinashortperiodoftimeNOTEThistypeofrepeatabilityincludesvariabilityduetosamplinganddispersion.3.1.16reproducibility(method)⟨particlesizeanalysis⟩closenessofagreementbetweenmultiplemeasurementresultsofagivenpropertyindifferentaliquotsofasample,preparedandexecutedbydifferentoperatorsinsimilarinstrumentsaccordingtothesamemethod3.1.17scattering⟨particlesizeanalysis⟩changeinpropagationoflightattheinterfaceoftwomediahavingdifferentopticalproperties3.1.18scatteringangle⟨particlesizeanalysis⟩anglebetweentheprincipalaxisoftheincidentlightbeamandthescatteredlight3.1.19scatteringpatternangularpatternoflightintensity,I(θ),orspatialpatternoflightintensity,I(r),originatingfromscattering,ortherelatedenergyvaluestakingintoaccountthesensitivityandthegeometryofthedetectorelements3.1.20singlescatteringscatteringwherebythecontributionofasinglememberofaparticlepopulationtothetotalscatteringpatternremainsindependentoftheothermembersofthepopulation3.1.21singleshotanalysisanalysis,forwhichtheentirecontentofasamplecontainerisused3.1.22transmission⟨particlesizeanalysis⟩fractionofincidentlightthatremainsunattenuatedbytheparticlesNOTE1Transmissioncanbeexpressedasapercentage.NOTE2Whenexpressedasfractions,obscuration(3.1.10)plustransmissionequalunity.3.1.23widthofsizedistributionthewidthoftheparticlesizedistribution(PSD),expressedasthex90/x10ratioNOTEFornormal(Gaussian)sizedistributions,oftenthestandarddeviation(absolutevalue),σ,orthecoefficientofvariation(CV)isused.Then,about95%ofthepopulationofparticlesfallswithin±2σfromthemeanvalueandabout99,7%within±3σfromthemeanvalue.Thedifferencex90−x10correspondsto2,6σ.ISO13320:2009(E)©ISO2009–Allrightsreserved53.2SymbolsAiextinctionefficiencyofsizeclassiCparticulateconcentration,volumefractionCVcoefficientofvariationffocallengthoflensisquarerootof−1inphotocurrentofdetectorelement,nI(θ)angularintensitydistributionoflightscatteredbyparticles(scatteringpattern)IhintensityofhorizontallypolarizedlightatagivenangleI(r)spatialintensitydistributionoflightscatteredbyparticlesonthedetectorelements(measuredscatteringpatternbydetector)IvintensityofverticallypolarizedlightatagivenangleJifirstorderBesselFunctionkwavenumberinmedium:2πnm/λkpimaginary(absorption)partoftherefractiveindexofaparticleladistancefromscatteringobjecttodetectorlbilluminatedpathlengthcontainingparticlesLnvectorofphotocurrents(i1,i2...in)mrelrelative,complexrefractiveindexofparticletomediumMmodelmatrix,containingcalculateddetectorsignalsperunitvolumeofparticlesinallsizeclassesnmrealpartofrefractiveindexofmediumnprealpartofrefractiveindexofparticlenpcomplexrefractiveindexofparticleOobscuration(1−transmission);onlytrueforsinglescatteringrradialdistancefromfocalpointinfocalplaneVvectorofvolumecontentinsizeclasses(V1,V2…Vi)Vivolumecontentofsizeclassivvelocityofparticlesindrydisperserxparticlediameterxigeometricmeanparticlesizeofsizeclassix50medianparticlediameter;hereusedonavolumetricbasis,i.e.50%byvolumeoftheparticlesaresmallerthanthisdiameterand50%arelargerx10particlediametercorrespondingto10%ofthecumulativeundersizedistribution(herebyvolume)x90particlediametercorrespondingto90%ofthecumulativeundersizedistribution(herebyvolume)αdimensionlesssizeparameter:πxnm/λ∆Q3,ivolumefractionwithinsizeclassiISO13320:2009(E)6©ISO2009–Allrightsreservedθscatteringanglewithrespecttoforwarddirectionθmanglewithrespecttoperpendicularatboundaryforalightbeaminmedium(asusedinSnell'slaw;see3.1.13,Note)θpanglewithrespecttoperpendicularatboundaryforalightbeaminparticle(asusedinSnell'slaw;see3.1.13,Note)λwavelengthofilluminatinglightsourceinvacuumσstandarddeviationωangularfrequency4PrincipleAsample,dispersedatanadequateconcentrationinasuitableliquidorgas,ispassedthroughthebeamofamonochromaticlightsource,usuallyalaser.Thelightscatteredbytheparticles,atvariousangles,ismeasuredbymulti-elementdetectors,andnumericalvaluesrelatingtothescatteringpatternarerecordedforsubsequentanalysis.Thesenumericalscatteringvaluesarethentransformed,usinganappropriateopticalmodelandmathematicalprocedure,toyieldtheproportionofthetotalvolumeofparticlestoadiscretenumberofsizeclassesformingavolumetricparticlesizedistribution(PSD).ThelaserdiffractiontechniqueforthedeterminationofPSDsisbasedonthephenomenonthatparticlesscatterlightinalldirectionswithanintensitypatternthatisdependentonparticlesize.Figure1illustratesthisdependencyinthescatteringpatternsfortwosizesofsphericalparticles.Inadditiontoparticlesize,particleshapeandtheopticalpropertiesoftheparticulatematerialinfluencethescatteringpattern.a)b)Figure1—Scatteringpatternfortwosphericalparticles:theparticlegeneratingpatterna)istwiceaslargeastheonegeneratingpatternb)(simulatedimagesforclarity)5LaserdiffractioninstrumentAset-upforalaserdiffractioninstrumentisgiveninFigure2.InthisFourierset-up,alightsource(typicallyalaserorothernarrow-wavelengthsource)isusedtogenerateamonochromatic,coherent,parallelbeam.Thisisfollowedbyabeamprocessingunit,usuallyabeamexpanderwithintegratedfilter,producinganextendedandnearlyidealbeamtoilluminatethedispersedparticles.ISO13320:2009(E)©ISO2009–Allrightsreserved7Key1obscuration/opticalconcentrationdetector2scatteredbeam3directbeam4fourierlens5scatteredlightnotcollectedbylens46ensembleofdispersedparticles7lightsource(e.g.laser)8beamprocessingunit9workingdistanceoflens410multi-elementdetector11focaldistanceoflens4NOTEForexplanationsofsymbols,see3.2.Figure2⎯Fourierset-upofalaserdiffractioninstrumentAsampleofparticles,dispersedatanadequateconcentration,ispassedthroughthelightbeaminameasuringzonebyatransportingmedium(gasorliquid).Thismeasuringzoneshouldbewithintheworkingdistanceofthelensused.Sometimes,theparticlestreaminaprocesspassesdirectlythroughthelaserbeamformeasurement.Thisisthecaseinthemeasurementofspraysandaerosols.Inothercases(e.g.whenmeasuringemulsions,pastesandpowders),samplescanbedispersedinfluidsandcausedtoflowthroughthemeasurementzone.Oftendispersants(wettingagents;stabilizers)and/ormechanicalforces(agitation;sonication)areappliedfordeagglomerationofparticlesandforstabilizationofthedispersion.Fortheseliquiddispersions,arecirculationsystemismostcommonlyused,consistingofanopticalmeasuringcell,adispersionbathusuallyequippedwithstirrerandultrasonicelements,apumpandtubing.Drypowderscanalsobeconvertedintoaerosolsthroughapplicationofdrypowderdispersers,whichapplymechanicalforcesfordeagglomeration.Here,adosingdevicefeedsthedisperserwith,ideally,anear-constantmassflowofsample.Thedisperserusestheenergyofacompressedgasorthedifferentialpressuretoavacuumtodispersetheparticles.Itoutputsanaerosolthatisblownthroughthemeasuringzone,usuallyintotheinletofavacuumpipethatcollectstheparticles.Coarse,non-agglomeratedpowderscanbetransportedthroughthemeasurementzonebygravity.Therearetwopositionsinwhichtheparticlescanenterthelaserbeam.IntheFourieropticscase,theparticlesentertheparallelbeambeforeandwithintheworkingdistanceofthecollectinglens[seeFigure3a)].Thisallowsforthemeasurementofspatiallyextendedparticlesystems.InthereverseFourieropticscase,theparticlesenterbehindthelensand,thus,inaconvergingbeam[seeFigure3b)].TheadvantageoftheFourierset-upisthatareasonablepathlengthforthesampleisallowedwithintheworkingdistanceofthelens.ThereverseFourierset-updemandssmallpathlengthsbutprovidesonesolutionthatenablesthemeasurementofscatteredlightatlargerangles.Theinteractionoftheincidentl