1、BRITISH STANDARD BS EN 13466-2:2001 Fertilizers Determination of water content (Karl Fischer methods) Part 2: 2-propanol as extracting medium The European Standard EN 13466-2:2001 has the status of a British Standard ICS 65.080 NO COPYING WITHOUT BSI PERMISSION EXCEPT AS PERMITTED BY COPYRIGHT LAWBS
2、 EN 13466-2:2001 This British Standard, having been prepared under the direction of the Materials and Chemicals Sector Policy and Strategy Committee, was published under the authority of the Standards Policy and Strategy Committee on 10 April 2002 BSI 10 April 2002 ISBN 0 580 39473 5 National forewo
3、rd This British Standard is the official English language version of EN 13466-2:2001. The UK participation in its preparation was entrusted to Technical Committee CII/37, Fertilizers and related chemicals, which has the responsibility to: A list of organizations represented on this committee can be
4、obtained on request to its secretary. Cross-references The British Standards which implement international or European publications referred to in this document may be found in the BSI Standards Catalogue under the section entitled “International Standards Correspondence Index”, or by using the “Fin
5、d” facility of the BSI Standards Electronic Catalogue. A British Standard does not purport to include all the necessary provisions of a contract. Users of British Standards are responsible for their correct application. Compliance with a British Standard does not of itself confer immunity from legal
6、 obligations. aid enquirers to understand the text; present to the responsible 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
7、This document comprises a front cover, an inside front cover, the EN title page, pages 2 to 10, an inside back cover 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 CommentsEUROPEANSTAN
8、DARD NORMEEUROPENNE EUROPISCHENORM EN134662 October2001 ICS65.080 Englishversion FertilizersDeterminationofwatercontent(KarlFischer methods)Part2:2propanolasextractingmedium EngraisDterminationdelateneureneau(MthodesKarl Fischer)Partie2:2propanolcommemilieudextraction DngemittelBestimmungdesWasserge
9、haltes(Karl FischerVerfahren)Teil2:2PropanolalsExtraktionsmittel ThisEuropeanStandardwasapprovedbyCENon18August2001. CENmembersareboundtocomplywiththeCEN/CENELECInternalRegulationswhichstipulatetheconditionsforgivingthisEurope an Standardthestatusofanationalstandardwithoutanyalteration.Uptodatelists
10、andbibliographicalreferencesconcernings uchnational standardsmaybeobtainedonapplicationtotheManagementCentreortoanyCENmember. ThisEuropeanStandardexistsinthreeofficialversions(English,French,German).Aversioninanyotherlanguagemadebytra nslation undertheresponsibilityofaCENmemberintoitsownlanguageandn
11、otifiedtotheManagementCentrehasthesamestatusasthe official versions. CENmembersarethenationalstandardsbodiesofAustria,Belgium,CzechRepublic,Denmark,Finland,France,Germany,Greece, Iceland,Ireland,Italy,Luxembourg,Netherlands,Norway,Portugal,Spain,Sweden,SwitzerlandandUnitedKingdom. EUROPEANCOMMITTEEF
12、ORSTANDARDIZATION COMITEUROPENDENORMALISATION EUROPISCHESKOMITEEFRNORMUNG ManagementCentre:ruedeStassart,36B1050Brussels 2001CEN Allrightsofexploitationinanyformandbyanymeansreserved worldwideforCENnationalMembers. Ref.No.EN134662:2001EEN134662:2001(E) 2 Contents page Foreword3 Introduction .4 1 Sco
13、pe 5 2 Normativereferences 5 3 Principle5 4 Reagents.5 5 Apparatus .5 6 InstallationandtestoftheKarlFischertitrator 6 7 Sampling.6 8 Procedure .6 9 Calculationandexpressionofresults. 8 10 Precision.8 11 Testreport 8 Bibliography 10EN134662:2001(E) 3 Foreword ThisEuropeanStandardhasbeenpreparedbyTech
14、nicalCommitteeCEN/TC260“Fertilizersandliming materials“,thesecretariatofwhichisheldbyDIN. ThisEuropeanStandardshallbegiventhestatusofanationalstandard,eitherbypublicationofanidenticaltextor byendorsement,atthelatestbyApril2002,andconflictingnationalstandardsshallbewithdrawnatthelatestby April2002. A
15、ccordingtotheCEN/CENELECInternalRegulations,thenationalstandardsorganizationsofthefollowing countriesareboundtoimplementthisEuropeanStandard:Austria,Belgium,CzechRepublic,Denmark,Finland, France,Germany,Greece,Iceland,Ireland,Italy,Luxembourg,Netherlands,Norway,Portugal,Spain,Sweden, Switzerlandandt
16、heUnitedKingdom.EN134662:2001(E) 4 Introduction Thewatercontentoffertilizershasasignificanteffectontheirqualityand,especially,theirstorageandhandling properties. Watercanbepresentinanumberofformssuchasfreewater,boundwaterandwaterofcrystallization.Itisoften importanttobeabletodistinguishbetweenthesef
17、ormsofwater.Thegravimetricmethodsfordeterminationof waterstandardizedinEN12048andEN12049haveonlylimitedapplicability. TheKarlFischermethodisapplicabletoawiderangeoffertilizers.However,thereareseveralvariationstothe basictechnique,differentformulationsoftheKarlFischerreagentsarecommerciallyavailablea
18、ndanumberof differentsolventscanbeused.Inthisstandard,methanoland2propanolareusedasextractingmediato distinguishbetweenthedifferentformsofwaterpresentinfertilizers. EN13466“FertilizersDeterminationofwatercontent(KarlFischermethods)“consistsoftwoparts: Part1:Methanolasextractingmedium Part2:2propanol
19、asextractingmedium Asexamplesofthedifferencebetweenmethanoland2propanolasextractingmediamethanolgivesaresultwhich isacombinationoffreewaterandextractedwaterofcrystallizationfromthefollowingcomponentsoffertilizers: calciumnitratetetrahydrate(Ca(NO 3 ) 2 4H 2 O);calciumhydrogenphosphatedihydrate(CaHPO
20、 4 2H 2 O);calcium sulfatedihydrate(gypsum,CaSO 4 2H 2 O)calciumsulfatehemihydrate(CaSO 4 0,5H 2 O);magnesiumsulfate heptahydrate(MgSO 4 7H 2 O);potassiumchloridemagnesiumsulfatewater(1/1/2,75,Kainite,KCl MgSO 4 2,75H 2 O);potassiummagnesiumsulfatehexahydrate(Schoenite,K 2 SO 4 MgSO 4 6H 2 O);potass
21、ium magnesiumsulfatetetrahydrate(Leonite,K 2 SO 4 MgSO 4 4H 2 O);potassiumsulfatecalciumsulfatemonohydrate (Syngenite,K 2 SO 4 CaSO 4 H 2 O);potassiumchloridemagnesiumchloridehexahydrate(Carnallite,KCl MgCl 2 6H 2 O);magnesiumnitratehexahydrate(Mg(NO 3 ) 2 6H 2 O). Extractionwith2propanolgivesaresul
22、twhichisacombinationoffreewaterandextractedwaterofcrystallization fromthefollowingcomponentsoffertilizers:calciumnitratetetrahydrate(Ca(NO 3 ) 2 4H 2 O);magnesiumsulfate heptahydrate(MgSO 4 7H 2 O);potassiumchloridemagnesiumchloridehexahydrate(Carnallite,KClMgCl 2 6H 2 O); magnesiumnitratehexahydrat
23、e(Mg(NO 3 ) 2 6H 2 O).EN134662:2001(E) 5 1Scope ThisEuropeanstandardspecifiesaKarlFischertitrimetricmethodforthedeterminationofthewatercontentof fertilizersbasedontheuseof2propanolasextractingmedium. Themethodisapplicabletoallsolidmineralfertilizers.Theresult(KFPwater)includes“free“waterand extracte
24、d waterofcrystallizationfromthefollowingcomponentsoffertilizers:calciumnitratetetrahydrate(Ca(NO 3 ) 2 4H 2 O); magnesiumsulfateheptahydrate(MgSO 4 7H 2 O);potassiumchloridemagnesiumchloridehexahydrate(Carnallite, KClMgCl 2 6H 2 O);magnesiumnitratehexahydrate(Mg(NO 3 ) 2 6H 2 O). 2 Normativereferenc
25、es ThisEuropeanStandardincorporatesbydatedorundatedreference,provisionsfromotherpublications.These normativereferencesarecitedattheappropriateplacesinthetext,andthepublicationsarelistedhereafter.For datedreferences,subsequentamendmentstoorrevisionsofanyofthesepublicationsapplytothisEuropean Standard
26、onlywhenincorporatedinitbyamendmentorrevision.Forundatedreferencesthelatesteditionofthe publicationreferredtoapplies(includingamendments). EN1482, Samplingofsolidfertilizersandlimingmaterials. 3Principle Extractionofwaterfromthefertilizerinto2propanol,separationoftheclearsolutionandtitrationoftheext
27、racted waterwithaKarlFischerreagent,previouslystandardizedbytitrationwithaknownmassofwater. 4Reagents 4.1 General Allreagentsshallbeofrecognizedanalyticalgrade. 4.2 2propanol ,containinglessthanamassconcentrationof250mg/lwater. 4.3 KarlFischerreagent ,equivalencefrom1mgto5mgwater/mlreagent(seeTable1
28、). 4.4 Sodiumtartratedihydrate Na 2 C 4 H 4 O 6 2H 2 O(15,66%massfractionofwater). SodiumtartratedihydrateNa 2 C 4 H 4 O 6 2H 2 Ocanbestoredover60%H 2 SO 4 inadesiccator.Checkthewater contentbydryingatabout150C. 5Apparatus Ordinarylaboratoryapparatusandglasswareandinparticularthefollowing: 5.1 Balan
29、ce,capableofweighingtothenearest0,0001g. 5.2 Centrifugecapableofoperatingatarateof3500min 1 . 5.3 Centrifugetubes ,diameter4,5cm,height10cmfittedwithrubberstoppers.EN134662:2001(E) 6 5.4Dispersing apparatus :turbinetype,minimumrotationalfrequency9500min 1 ,suitableforintroductioninto centrifugetubes
30、(5.3),forinstanceUltraTurrax 1 5.5 KarlFischertitrator NOTE ThereareseveraltitratorsonthemarketfortheKarlFischermethod. 6 InstallationandtestoftheKarlFischertitrator Followtheinstructionmanualfortheparticulartitratorused. 7Sampling CarryoutsamplinginaccordancewithEN1482. 8Procedure 8.1Calibrationoft
31、heKarlFischerreagent Titrateaknownamountofwaterorsodiumtartratedihydrate(4.4)accuratelyweighedtothenearest0,0001g followingtheinstructionmanualforthetitrator. NOTE Calibrationfrequencyshouldbeadaptedtothefrequencyofanalysis. 8.2Drift Controlthediffusionofwaterfromtheairintothetitrationvesselduringth
32、edeterminationfollowingtheinstruction manualforthetitrator.Takeaccountofanyrecordeddrift( m d )whenexpressingresults. 8.3Testportion Weightothenearest0,0001gatestportionofthetestsampleinaccordancewithclause7andTable1directly intothepreviouslydriedandtaredcentrifugetube(5.3). Table1Massoftestportion
33、Massoftestportion Expectedwatercontent massfractionin% titreofKFReagent 5mg/ml titreofKFReagent 2mg/ml 20to50 1g 1 UltraTurraxS25 equippedwithdispersingturbineS25KR18Gisanexampleofequipmentcommercially available.ThisinformationisgivenfortheconvenienceofusersofthisEuropeanStandardanddoesnotconstitute
34、 anendorsementbyCENoftheseproducts.EN134662:2001(E) 7 8.4Extraction Add25mlof2propanol(4.2)withacalibratedpipettetothetestportioninthecentrifugetube.Insertthedispersing apparatus(5.4)ensuringthatthedistancefromanypartofthedispersingtooltotheinnersurfaceofthecentrifuge tubeisgreaterthanthegrainsizeof
35、thefertilizer. Placethedispersingtoolneartothesurfaceofthefertilizerlayer.Dispersefor60satroomtemperatureat 9500min 1 atleast. Makesurethatthetemperatureduringthedispersionextractiondoesnotexceed40Cor,inthecaseoffertilizer containingmagnesiumsulfate,25C. Repeatthedispersionforafurther60sifthefertili
36、zerhasnotbeencompletelydispersedinthefirstoperation. Repeattheextractionifthedispersionisstillnotcomplete. NOTE Thedispersioncanbecontrolledacoustically;theturbinepitchchangesoncethedispersioniscomplete. 8.5Separation Removethedispersionapparatusfromthecentrifugetubeandstopperthelatterwiththerubbers
37、topper. Centrifugethetubefor5min.Repeatfor5minifthesupernatantliquidisnotclear. 8.6Titration Introduce5,0mloftheclearsolution(8.3)intothereactionvesselofthetitrator(5.5).Startstirring.Titratewiththe KarlFischerreagent(4.3)untiltheequivalencepointisreached,followingtheinstructionmanualforthetitrator.
38、 Recordthemass m s , inmilligramsofwater,indicatedbythetitrator. 8.7Blanktest Carryoutablanktestfollowingtheprocedurespecifiedin8.2butomittingthetestportion.Recordthemass m b . 8.8Replication Repeattheproceduredescribedin8.1to8.6usingasecondtestportionfromthesametestsample.Afterusethe dispersingtool
39、shouldbecleanedanddried. 8.9Alternativeprocedureforaseriesofsamples 8.9.1 Ifaserialanalysisiscontemplatedforseveralsamplesanalternativeproceduremaybeusedprovided enough2propanolcanbeheldinthetitratorreactionvesseltoaccomodateallthesamplesandtheensuing quantityofKarlFischerreagent.Theprocedureisasgiv
40、enin8.9.2to8.9.8. 8.9.2 Checkfordriftasdescribedin8.2. 8.9.3 Introduce5mlof2propanol(4.2). 8.9.4 AddtheKarlFischerreagentuntiltheequivalencepointisreached.Resetthetitratorreadingstozero. 8.9.5 Introduceexactly5mlofextractantresultingfromtheseparation(see8.5). 8.9.6 Titratetotheequivalencepointwhilst
41、stirring.Recordthereading.Resetthe readingstozero.Stopstirring. 8.9.7 Introduceafurther5mlofextractantresultingfromtheseparation(see8.5) .Repeattheprocedure describedin8.9.6. 8.9.8 Carryoutablanktestasdescribedin8.7.EN134662:2001(E) 8 9 Calculationandexpressionofresults Thewatercontentofthesample, w
42、 KFP ,expressedasmassfractioninpercent,inaccordancewiththeKarlFischer methodwith2propanolasextractingmediumisgivenbythefollowingequation: t d b s KFP 100 ) ( 5 m m m m w where m s isthemassofwaterinthesamplerecordedin8.6,inmilligrams; m b isthemassofwaterobtainedbyblanktest(8.7),inmilligrams; m d is
43、themassofwatermeasuredasper8.2,inmilligrams; m t isthemassofthetestportion,inmilligrams. Reportthemeanoftwodeterminations. 10Precision 10.1 Interlaboratorytest AninterlaboratorytestwascarriedoutinApril1997with15participatinglaboratoriesandfivedifferentfertilizer formulae.Theseformulaewere:ammoniumnitrate(AN)fromtwodifferentsources,calciumammoniumnitrate (CAN),NPKoftheformula12+12+17+2andThomasKali(PK).Foradditionalinformationsee1. 10.2 Repeatability Theabsolutedifferencebetweentwosingletestresultsobtainedwiththesamemethodonidenticaltestmate
