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1、GasChromatographystationarybedfluidWhatis“Chromatography”“colorwriting”theseparationofmixturesintotheirconstituentsbypreferentialadsorptionbyasolid”(RandomHouseCollegeDictionary,1988)“Chromatographyisaphysicalmethodofseparationinwhichthecomponentstobeseparatedaredi
2、stributedbetweentwophases,oneofthephasesconstitutinga______________oflargesurfacearea,theotherbeinga______thatpercolatesthroughoralongthestationarybed.”(Ettre&Zlatkis,1967,“ThePracticeofGasChromatography)gasApplicationsCompoundmustexistasa____atatemperaturethatcanb
3、eproducedbytheGCandwithstoodbythecolumn(upto450°C)AlcoholsinbloodAromatics(benzene,toluene,ethylbenzene,xylene)FlavorsandFragrancesPermanentgases(H2,N2,O2,Ar,CO2,CO,CH4)HydrocarbonsPesticides,Herbicides,PCBs,andDioxinsSolventsAdvantagesofGasChromatographyRequireson
4、lyverysmallsampleswithlittlepreparationGoodatseparatingcomplexmixturesintocomponentsResultsarerapidlyobtained(1to100minutes)VeryhighprecisionOnlyinstrumentwiththesensitivitytodetectvolatileorganicmixturesoflowconcentrationsEquipmentisnotverycomplex(sophisticatedove
5、n)ChromatogramofGasoline1.Isobutane2.n-Butane3.Isopentane4.n-Pentane5.2,3-Dimethylbutane6.2-Methylpentane7.3-Methylpentane8.n-Hexane9.2,4-Dimethylpentane10.Benzene11.2-Methylhexane12.3-Methylhexane13.2,2,4-Trimethylpentane14.n-Heptane15.2,5-Dimethylhe
6、xane16.2,4-Dimethylhexane17.2,3,4-Trimethylpentane18.Toluene19.2,3-Dimethylhexane20.Ethylbenzene21.m-Xylene22.p-Xylene23.o-XyleneTheoryofOperationVelocityofacompoundthroughthecolumndependsuponaffinityforthestationaryphaseAreaundercurveis______ofcompoundadso
7、rbedtostationaryphaseGasphaseconcentrationCarriergasmassProcessFlowSchematicCarriergas(nitrogenorhelium)SampleinjectionLongColumn(30m)Detector(flameionizationdetectororFID)HydrogenAirGasChromatographComponentsFlameIonizationDetectorColumnOvenInjectionPorttopviewfro
8、ntviewGasChromatographyFlameIonizationDetectorRespondstocompoundsthatproduce____whenburnedinanH2-airflameallorganiccompoundsLittleornoresponseto(