BS EN 13717-2002 Surface active agents - Determination of primary secondary and tertiary amino nitrogen - Potentiometric titration《表面活性剂 伯、仲、叔胺基氮的测定 电势滴定法》.pdf

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1、BRITISH STANDARD BS EN 13717:2002 Surface active agents Determination of primary, secondary and tertiary amino nitrogen Potentiometric titration The European Standard EN 13717:2002 has the status of a British Standard ICS 71.100.40 BS EN 13717:2002 This British Standard, having been prepared under t

2、he direction of the Materials and Chemicals Sector Policy and Strategy Committee, was published under the authority of the Standards Policy and Strategy Committee on 20 December 2002 BSI 20 December 2002 ISBN 0 580 40123 4 National foreword This British Standard is the official English language vers

3、ion of EN 13717:2002. The UK participation in its preparation was entrusted to Technical Committee CII/34, Methods of test for surface active agents, which has the responsibility to: A list of organizations represented on this committee can be obtained on request to its secretary. Cross-references T

4、he British Standards which implement international or European publications referred to in this document may be found in the BSI Catalogue under the section entitled “International Standards Correspondence Index”, or by using the “Search” facility of the BSI Electronic Catalogue or of British Standa

5、rds Online. This publication does not purport to include all the necessary provisions of a contract. Users are responsible for its correct application. Compliance with a British Standard does not of itself confer immunity from legal obligations. aid enquirers to understand the text; present to the r

6、esponsible international/European committee any enquiries on the interpretation, or proposals for change, and keep the UK interests informed; monitor related international and European developments and promulgate them in the UK. Summary of pages This document comprises a front cover, an inside front

7、 cover, the EN title page, pages 2 to 13 and a back cover. The BSI copyright date displayed in this document indicates when the document was last issued. Amendments issued since publication Amd. No. Date CommentsEUROPEANSTANDARD NORMEEUROPENNE EUROPISCHENORM EN13717 December2002 ICS71.100.40 English

8、version SurfaceactiveagentsDeterminationofprimary,secondaryand tertiaryaminonitrogenPotentiometrictitration AgentsdesurfaceDterminationdelateneurenazote sousformeamineprimaire,secondaireettertiaireTitrage potentiomtrique GrenzflchenaktiveStoffeBestimmungdesGehaltsan Primr,SekundrundTertirAminstickst

9、off PotentiometrischeTitration ThisEuropeanStandardwasapprovedbyCENon23October2002. CENmembersareboundtocomplywiththeCEN/CENELECInternalRegulationswhichstipulatetheconditionsforgivingthisEurope an Standardthestatusofanationalstandardwithoutanyalteration.Uptodatelistsandbibliographicalreferencesconce

10、rnings uchnational standardsmaybeobtainedonapplicationtotheManagementCentreortoanyCENmember. ThisEuropeanStandardexistsinthreeofficialversions(English,French,German).Aversioninanyotherlanguagemadebytra nslation undertheresponsibilityofaCENmemberintoitsownlanguageandnotifiedtotheManagementCentrehasth

11、esamestatusasthe official versions. CENmembersarethenationalstandardsbodiesofAustria,Belgium,CzechRepublic,Denmark,Finland,France,Germany,Greece, Iceland,Ireland,Italy,Luxembourg,Malta,Netherlands,Norway,Portugal,Spain,Sweden,SwitzerlandandUnitedKingdom. EUROPEANCOMMITTEEFORSTANDARDIZATION COMITEURO

12、PENDENORMALISATION EUROPISCHESKOMITEEFRNORMUNG ManagementCentre:ruedeStassart,36B1050Brussels 2002CEN Allrightsofexploitationinanyformandbyanymeansreserved worldwideforCENnationalMembers. Ref.No.EN13717:2002EEN13717:2002(E) 2 Contents page Foreword3 1 Scope 4 2 Normativereference . .4 3 Principle4 4

13、 Reagents.4 5 Apparatus .5 6 Samplingandpreparationofthesample 5 7 Procedure .5 8 Expressionofresults . .6 9 Precision.8 10 Testreport 8 AnnexA (informative) Instrumentsettings. 9 AnnexB (informative) Typicaltitrationcurves .10 AnnexC (informative) Resultsofinterlaboratorytest.11 Bibliography 13EN13

14、717:2002(E) 3 Foreword Thisdocument(EN13717:2002)hasbeenpreparedbyTechnicalCommitteeCEN /TC 276,“Surfaceactive agents“thesecretariatofwhichisheldbyAFNOR. ThisEuropeanStandardshallbegiventhestatusofanationalstandard,eitherbypublicationofanidenticaltextor byendorsement,atthelatestbyJune2003,andconflic

15、tingnationalstandardsshallbewithdrawnatthelatestby June2003. TheannexesA,BandCareinformative. AccordingtotheCEN/CENELECInternalRegulations,thenationalstandardsorganizationsofthefollowing countriesareboundtoimplementthisEuropeanStandard:Austria,Belgium,CzechRepublic,Denmark,Finland, France,Germany,Gr

16、eece,Iceland,Ireland,Italy,Luxembourg,Malta,Netherlands,Norway,Portugal,Spain, Sweden,SwitzerlandandtheUnitedKingdom.EN13717:2002(E) 4 1Scope ThisEuropeanStandardspecifiesthemethodsforthedeterminationofprimary,secondaryandtertiaryamino nitrogencontentinsurfaceactiveagentsbypotentiometrictitration. 2

17、 Normativereference ThisEuropeanStandardincorporatesbydatedorundatedreference,provisionsfromotherpublications.These normativereferencesarecitedattheappropriateplacesinthetextandthepublicationsarelistedhereafter.For datedreferences,subsequentamendmentstoorrevisionsofanyofthesepublicationsapplytothisE

18、uropean Standardonlywhenincorporatedinitbyamendmentorrevision.Forundatedreferencesthelatesteditionofthe publicationreferredtoapplies(includingamendments). ISO607, SurfaceactiveagentsanddetergentsMethodsofsampledivision 3Principle 3.1 Thesumofprimaryandsecondaryaminonitrogen Afterreactionoftheprimary

19、andsecondaryaminonitrogenwithcarbondisulfide,theresultingdithiocarbamicacids aretitratedwithsodiumhydroxidestandardvolumetricsolution(seealsoNOTEin7.1). 3.2 Thesumofsecondaryandtertiaryaminonitrogen AfterreactionoftheprimaryaminonitrogenwithsalicylaldehydetogiveaSchiffsbase,thesumofsecondaryand tert

20、iaryaminonitrogenisdeterminedbypotentiometrictitrationwithhydrochloricacidstandardvolumetricsolution. 3.3 Tertiaryaminonitrogen Afterreactionoftheprimaryandsecondaryaminonitrogenwithaceticacidanhydride,thetertiaryaminonitrogenis determinedbytitrationwithstandardtrifluoromethanesulfonicacidsolution.

21、NOTE Alternatively,areactionwithphenylisothiocyanateandasubsequenttitrationwithhydrochloricacidstandard volumetricsolutioncanbecarriedout. 4Reagents Duringtheanalysis,unlessotherwisespecified,useonlyreagentsofrecognizedanalyticalgradeandhavebeen checkedinadvanceastonotinterferewiththeanalyticalresul

22、ts. 4.1 Sodiumhydroxidestandardvolumetricsolution, c (NaOH)=0,1mol/l. 4.2 Carbondisulfide, purity99,7%(minimum). WARNING Thissubstanceishighlyflammableandtoxic.Itcausesseriousdamagetohealthby prolongatedexposurethroughinhalationandisapossibleriskofimpairedfertilityaswellasharmtothe unbornchild.Thiss

23、ubstanceirritatestoeyesandskin. 4.3 2Propanol, purity99,5%(minimum). 4.4 Hydrochloricacidstandardvolumetricsolution, c(HCl)=0,1mol/l,in2propanol.EN13717:2002(E) 5 4.5 Salicylaldehyde,purity99%(minimum). 4.6 Aceticacidanhydride, purity98,5%(minimum). 4.7 Trifluoromethanesulfonicacidstandardvolumetric

24、solution, c(HSO 3 CF 3 )=0,1mol/l,inglacialacetic acid. NOTE Perchloricacid, c(HClO 4 )=0,1mol/l,inglacialaceticacidcanalsobeused. 4.8 Glacialaceticacid, purity100%. 4.9 Phenolphthaleinsolution, r =1g/100ml,inethanol,asindicator. 4.10 Phenylisothiocyanate,purity98%(minimum). 5Apparatus Ordinarylabor

25、atoryapparatusandthefollowing. 5.1 Potentiometrictitratingapparatus,comprisingatitratorwithacombinedpHglasselectrode,a20mlplunger buretteandastirrer. NOTE AnexampleofinstrumentsettingsisgiveninAnnexA. 5.2 Beaker,capacity150ml. 5.3 Analyticalbalance, readingtothenearest0,1mg. 5.4 Magneticstirrer, wit

26、hhotplate. 5.5 Oven. 5.6 Pressurebottles, encasedinplastics,capacity250ml,withplasticsscrewcapsandpolytetrafluoroethylene (PTFE)seal. 5.7 Fumecupboard. 6 Samplingandpreparationofthesample ThelaboratorysampleofsurfaceactiveagentshallbepreparedandstoredinaccordancewithISO607. 7Procedure 7.1 Titrationo

27、ftheprimaryandsecondaryaminonitrogen Weighintothebeaker(5.2)aquantityofthesample( m 1 )tobetestedwhichcontainsabout0,5mmolto1mmolof totalbasenitrogentothenearest0,1mg.Dissolvethesamplein50mlof2propanol(4.3).Addafewdropsof phenolphthaleinsolution (4.9).Thenaddsodiumhydroxidestandardvolumetricsolution

28、 (4.1)untilthecolour changestofaintpink. Add5mlofcarbondisulfide(4.2)andstirfor1minatroomtemperature(workinafumecupboard). Immersetheelectrode,stirandtitratewithsodiumhydroxidestandardvolumetricsolution(4.1).EN13717:2002(E) 6 Recordtheamountconsumedattheequivalent(inflexion)point(volume V 1 );(seeAn

29、nexB). NOTE Toavoidtheuseofcarbondisulfide,thetestmethodinaccordancewithEN13716canbealternativelyappliedto determinethecontentoftotalbasenitrogen, w t ,theprimaryaminonitrogencontentiscalculatedbytheequation w 1 = w t w 2 when w 2 isdeterminedin7.2. 7.2 Titrationofthesecondaryandtertiaryaminonitroge

30、n Weighintothebeaker(5.2)anamountofthesample( m 2 )tobetestedwhichcontainsabout0,5mmolto1mmolof totalbasenitrogentothenearest0,1mg.Dissolvethesamplein50mlof2propanol(4.3). Add5mlofsalicylaldehyde(4.5)andheatat80Cfor15min(workinafumecupboard).Allowthesolutiontocool toroomtemperature. Immersetheelectr

31、ode,stirandtitratewithhydrochloricacidstandardvolumetricsolution(4.4). Recordtheconsumptionattheequivalent(inflexion)point(volume V 2 );(seeAnnexB). 7.3 Titrationofthetertiaryaminonitrogen(aceticacidanhydridemethod) Weighintoapressurebottle(5.6)aquantityofthesample(m 3 )tobetestedwhichcontainsabout0

32、,5mmol to1mmoloftotalbasenitrogentothenearest0,1mg.Dissolvethesamplein20mlofglacialaceticacid(4.8). Thenadd30mlofaceticacidanhydride(4.6). Sealthepressurebottle(5.6)securelyandheatat60Cintheoven(5.5)for30min. Allowtocooltoroomtemperature;openthepressurebottleandrinsedownthecapandthesidesofthebottlew

33、ith glacialaceticacid(4.8). Immersetheelectrode,stirandtitratewithtrifluoromethanesulfonicacidstandardvolumetricsolution(4.7). Recordtheconsumptionattheequivalent(inflexion)point(volume V 3 );(seeannexB). 7.4 Titrationofthetertiaryaminonitrogen(phenylisothiocyanatemethod) Weighintothebeaker(5.2)anam

34、ountofthesample( m 4 )tobetestedwhichcontainsabout0,5mmolto1mmolof totalbasenitrogentothenearest0,1mg.Dissolvethesamplein50mlof2propanol(4.3).Thenadd5mlof phenylisothiocyanate(4.10)andheatthesolutionat60Cfor30min(workinafumecupboard).Allowthesolution tocooltoroomtemperature. Immersetheelectrode,stir

35、andtitratewithhydrochloricacidstandardvolumetricsolution(4.4). Recordtheconsumptionattheequivalent(inflexion)point(volume V 4 );(seeAnnexB). 8 Expressionofresults 8.1 Calculationofthesumofprimaryandsecondaryaminonitrogen Calculatethesumofprimaryandsecondaryaminonitrogen, w 1 ,expressedasgramsper 100

36、 g,bythe equation(1): 000 1 100 1 1 1 1 1 = m M f c V w (1)EN13717:2002(E) 7 where V 1 isthevolumeofsodiumhydroxidestandardvolumetricsolution(4.1)accordingto7.1,inmillilitres; c 1 istheconcentrationofthesodiumhydroxidestandardvolumetricsolution(4.1),inmolesperlitre; f 1 isthefactorofthesodiumhydroxi

37、destandardvolumetricsolution(4.1); M isthemolarmassofnitrogen, M=14g/mol; m 1 isthemassofsampleaccordingto7.1,ingrams. 8.2 Calculationofthesumofsecondaryandtertiaryaminonitrogen Calculatethesumofsecondaryandtertiaryaminonitrogen, w 2 ,expressedasgramsper 100 g,bythe equation(2): 000 1 100 2 2 2 2 2

38、= m M f c V w (2) where V 2 isthevolumeofhydrochloricacidstandardvolumetricsolution(4.4)accordingto7.2,inmillilitres; c 2 istheconcentrationofhydrochloricacidstandardvolumetricsolution(4.4),inmolesperlitre; f 2 isthefactorofthehydrochloricacidstandardvolumetricsolution(4.4); M isthemolarmassofnitrog

39、en, M=14g/mol; m 2 isthemassofsampleaccordingto7.2,ingrams. 8.3 Calculationofthetertiaryaminonitrogen a) Calculatethetertiaryaminonitrogencontent, w 3 ,expressedasgramsper100g,bytheequation(3): 000 1 100 3 3 3 3 3 = m M f c V w (3) where V 3 isthevolumeoftrifluoromethanesulfonicacidstandardvolumetri

40、csolution (4.7)accordingto 7.3,in millilitres; c 3 isthesolutionconcentrationofthetrifluoromethanesulfonicacidstandardvolumetricsolution(4.7),in molesperlitre; f 3 isthefactorofthetrifluoromethanesulfonicacidstandardvolumetricsolution(4.7); M isthemolarmassofnitrogen, M=14g/mol; m 3 isthemassofthesa

41、mpleaccordingto7.3,ingrams.EN13717:2002(E) 8 b) Calculatethetertiaryaminonitrogencontent, w 4 ,expressedasgramsper100g,bytheequation(4): 000 1 100 4 4 4 4 4 = m M f c V w (4) where V 4 isthevolumeofhydrochloricacidstandardvolumetricsolution(4.4)accordingto7.4,inmillilitres; c 4 istheconcentrationoft

42、hehydrochloricacidstandardvolumetricsolution(4.4)inmolesperlitre; f 4 isthefactorofthehydrochloricacidstandardvolumetricsolution(4.4); M isthemolarmassofnitrogen, M=14g/mol; m 4 isthemassofsampleaccordingto7.4,ingrams. Theresultsshallbegiventotwodecimalplaces. 9Precision 9.1 Repeatabilitylimit Theab

43、solutedifferencebetweentwoindependentsingletestresults,obtainedusingthesamemethodonidentical testmaterialinthesamelaboratorybythesameoperatorusingthesameequipmentwithinashortintervaloftime, willnotexceedtherepeatabilitylimit, r,inmorethan5%ofcases. TypicalprecisiondataobtainedinaringtestaregiveninAnnexC. 9.2Reproducibility limit Theabsolutedifferencebetweentwosingletestresults,obtainedusingthesamemethodonidenticaltes

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