EPA METHOD 3600C Cleanup

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1、METHOD3600CCLEANUP1.0SCOPEANDAPPLICATION1.1Method3600providesgeneralguidanceonselectionofcleanupmethodsthatareappropriateforthetargetanalytesofinterest.Cleanupmethodsareappliedtotheextractspreparedbyoneoftheextractionmethods,toeliminatesampleinterferences.1.2T

2、hefollowingtableliststhecleanupmethodsandprovidesabriefdescriptionofthetypeofcleanup.MethodNo.MethodNameCleanupType3610AluminaCleanupAdsorption3611AluminaCleanupandSeparationofAdsorptionPetroleumWastes3620FlorisilCleanupAdsorption3630SilicaGelCleanupAdsorption

3、3640Gel-PermeationCleanup(GPC)Size-Separation3650Acid-BasePartitionCleanupAcid-BasePartitioning3660SulfurCleanupOxidation/Reduction3665SulfuricAcid/PermanganateOxidation/ReductionCleanup1.3Thepurposeofapplyingacleanupmethodtoanextractistoremoveinterferencesand

4、highboilingmaterialthatmayresultin:@errorsinquantitation(datamaybebiasedlowbecauseofanalyteadsorptionintheinjectionportorfrontoftheGCcolumnorbiasedhighbecauseofoverlapwithaninterferencepeak);@falsepositivesbecauseofinterferencepeaksfallingwithintheanalytereten

5、tiontimewindow;@falsenegativescausedbyshiftingtheanalyteoutsidetheretentiontimewindow;@rapiddeteriorationofexpensivecapillarycolumns;and,@instrumentdowntimecausedbycleaningandrebuildingofdetectorsandionsources.1.4Thefollowingtechniqueshavebeenappliedtoextractp

6、urification:adsorptionchromatography;partitioningbetweenimmisciblesolvents;gelpermeationchromatography;oxidationofinterferingsubstanceswithacid,alkali,oroxidizingagents.Thesetechniquesmaybeusedindividuallyorinvariouscombinations,dependingontheextentandnatureof

7、theco-extractives.1.5Mostextractsofsoilandwasterequiresomedegreeofcleanup,whereas,cleanupforwaterextractsmaybeunnecessary.Highlycontaminatedextracts(e.g.sampleextractsofoilywasteorsoilcontainingoilyresidue)oftenrequireacombinationofcleanupmethods.Forexample,wh

8、enanalyzingfororganochlorinepesticidesandPCBs,itmaybenecessarytousegelpermeationCD-ROM3600C-1Revision3December1996chromatography(GPC),toeliminatethehighboilingmaterialandamicroalum