EPA METHOD 3510C Separatory Funnel Liquid-Liquid Extraction

《EPA METHOD 3510C Separatory Funnel Liquid-Liquid Extraction》由会员上传分享，免费在线阅读，更多相关内容在行业资料-天天文库。

1、METHOD3510CSEPARATORYFUNNELLIQUID-LIQUIDEXTRACTION1.0SCOPEANDAPPLICATION1.1Thismethoddescribesaprocedureforisolatingorganiccompoundsfromaqueoussamples.Themethodalsodescribesconcentrationtechniquessuitableforpreparingtheextractfortheappropriatedeterminativemeth

2、odsdescribedinSection4.3ofChapterFour.1.2Thismethodisapplicabletotheisolationandconcentrationofwater-insolubleandslightlywater-solubleorganicsinpreparationforavarietyofchromatographicprocedures.1.3Thismethodisrestrictedtousebyorunderthesupervisionoftrainedanal

3、ysts.Eachanalystmustdemonstratetheabilitytogenerateacceptableresultswiththismethod.2.0SUMMARYOFMETHOD2.1Ameasuredvolumeofsample,usually1liter,ataspecifiedpH(seeTable1),isseriallyextractedwithmethylenechlorideusingaseparatoryfunnel.2.2Theextractisdried,concentr

4、ated(ifnecessary),and,asnecessary,exchangedintoasolventcompatiblewiththecleanupordeterminativemethodtobeused(seeTable1forappropriateexchangesolvents).3.0INTERFERENCES3.1RefertoMethod3500.3.2Thedecompositionofsomeanalyteshasbeendemonstratedunderbasicextractionc

5、onditions.Organochlorinepesticidesmaydechlorinate,phthalateestersmayexchange,andphenolsmayreacttoformtannates.ThesereactionsincreasewithincreasingpH,andaredecreasedbytheshorterreactiontimesavailableinMethod3510.Method3510ispreferredoverMethod3520fortheanalysis

6、oftheseclassesofcompounds.However,therecoveryofphenolsmaybeoptimizedbyusingMethod3520,andperformingtheinitialextractionattheacidpH.4.0APPARATUSANDMATERIALS4.1Separatoryfunnel-2-liter,withpolytetrafluoroethylene(PTFE)stopcock.4.2Dryingcolumn-20mmIDPyrex®chromat

7、ographiccolumnwithPyrex®glasswoolatbottomandaPTFEstopcock.NOTE:Frittedglassdiscsaredifficulttodecontaminateafterhighlycontaminatedextractshavebeenpassedthrough.Columnswithoutfritsmaybepurchased.UseasmallpadofPyrex®glasswooltoretaintheadsorbent.Prewashtheglassw

8、oolpadwith50mLofacetonefollowedby50mLofelutionsolventpriortopackingthecolumnwithadsorbent.CD-ROM3510C-1Revision3December19964.3Kuderna-Danish(K-D)apparatus.4.3.1Concentratortube-10