熱脫附是一種廣泛使用的技術(shù)，它能將揮發(fā)性和半揮發(fā)性化合物從各種基質(zhì)中萃取和分離出來。它可以作為一種空氣監(jiān)測技術(shù)（室內(nèi)、室外、車間、轎廂、呼吸等等），也可以是分析土壤、聚合物、包裝材料、食品、調(diào)料、化妝品、煙草、建筑材料、藥物和消費品的有效工具。實際上，幾乎任何含有揮發(fā)性有機(jī)物的樣品都能使用該技術(shù)進(jìn)行分析。全自動熱脫附食品分析和香料分析的理想選擇非常廣泛的應(yīng)用半導(dǎo)體和塑料行業(yè)中固體樣品檢測"移動烤箱"獨特技術(shù)容易安裝在氣相色譜儀進(jìn)樣口上方，方便快速安裝和拆除智能樣品傳送通過CTCPAL直接從樣品管熱萃取樣品到GC進(jìn)樣口加熱爐溫度高達(dá)350℃特制聚四氟乙烯插頭和TDAS樣品管密封圈無加熱傳送線或閥門切換-無殘留適用于大體積進(jìn)樣(liquidN2orliquidCO2coolingrequired)CycleComposer軟件控制可配備AgilentChemStationorThermoFinniganXcalibur插件安裝TDAS后，仍然具有CTC所有的已有液體進(jìn)樣、頂空進(jìn)樣、SPME和SPDE等模塊的功能.性能描述系統(tǒng)按照如下操作運行，首先解吸小瓶,開啟脫附管壓蓋,通過PAL的進(jìn)樣單元將樣品管從抽樣托盤運送到加熱器進(jìn)口。盡快將吸附管放入加熱爐,進(jìn)樣單元將吸附管推下，刺破吸附管兩端。加熱爐底部裝有針頭,注入樣品到PTV.承氣流入閥門開關(guān),并通過解吸管傳送到冷卻的PTV.所有樣品都被聚集到冷卻的襯墊上。經(jīng)過3-5分鐘,在高溫下脫附,PAL把熱脫附單元從進(jìn)樣口移開.此時,載氣切入進(jìn)樣口,使之不再經(jīng)過吸附樣品管.經(jīng)過短暫平衡時,PTV進(jìn)樣口迅速升高到它的最高溫度，如果在加熱時你選擇PTV在不分流模式，它將提供最高靈敏度?，F(xiàn)在吸附管可以再TDAS加熱爐里繼續(xù)設(shè)定的步驟，否則吸附管將會運回托盤.選擇適當(dāng)TDAS參數(shù)(例如,解吸溫度、解吸時間),也可能是控制萃取樣品的數(shù)量以及分子量分布.熱脫附應(yīng)用實例采用熱脫附系統(tǒng)測定三鹵代甲烷(THM)在游泳館空氣中含量.CHROMTECH(t201e)TDAS2000直接熱萃取應(yīng)用.CHROMTECH,04/2004(t401e)熱脫附氣相色譜分析高沸點、高分子量化合物04/2004(T402e).TDAS2000:TransportsdesorptionvialsautomaticlyviainjectionunitIdealforfoodflavoranalysesSolidsampleanalysesforsemiconductorplasticsindustriesEasytouseforgassamples,usingpre-filledadsorptiontubesSamplecapacityofupto296samplesNotransferlinesnoswitchingvalves.NocarryoverCrimpedsamplecontainer.NocontaminationofsampleEasymountingontopofGC.QuickinstallationremovalSmartvialtransportbyPALSystemDirectthermalextractionfromsamplevialtoGCinjector.Heateroventemperatureofupto350'CAdaptabletoexistingPTVinjectorsSoftwareintegratedwithHP/AgilentChemStationorThermoFinniganXcaliburDescriptionCHROMTECHisknownforitsreliableautomationproducts.Basedonthatreputation,wehavedesignedaneasilyattachablethermaldesorptionsystem.Atthesametime,theCombiPALstillperformsitsheadspace,SPMEliquidinjections.Itcanbetransformedtoathermaldesorptionsysteminfiveminutesorless.GivenCHROMTECH'sbackgroundinautomation,ourfocusisonlarge-samplecapacity.Upto294samplescanbeanalyzedusingoursystem.ThePALTDASfeaturesaunique,retractabledesorptionheaterthatismountedontopoftheGCinjector.Noheatedtransferlinesand/orswitchingvalvesareinitsflowpath.Thebodyofthethermaldesorptionunitretracts,sothaterrorsrelatedtosamplecontaminationlowreproducibilityareeliminated.Generally,PTVinjectors-cooledbyliquidnitrogenorCO2-areusedinconjunctionwithoursystemforthermaldesorptionanalysis.Thesystemworksasfollows.First,desorptionvials,crimpedwithregularcaps,aretransportedfromthesampletraytotheheaterinletportbythePAL'sinjectionunit.Assoonasthevialisplacedintotheheater,theinjectionunitpushesthevialheaterdownwards,piercingbothvialends.Thebottomoftheheater,whichisfittedwithasyringeneedle,injectsthesampleintothePTVwhentheheaterispusheddown.Thecarriergasflowthenswitchesdirection,passingthroughthedesorptionvialontothecooledPTV.Allanalytesaretherebyrefocusedontothecooledliner.Aftera3-5minutedesorptionatahightemperature,thePALwillmovethethermaldesorptionunitoutoftheinlet.Atthispoint,theflowwillberedirectedbacktotheinlet,sothatitnolongerpassesthroughthesample.Afterashortequilibrationtime,thePTVinletwillheatrapidlytoitsmaximumtemperature.IfyouchoosetodotheheatingwhilethePTVisinsplitlessmode,itwillprovidemaximumsensitivity.TDAS2000:DirectinjectionintoPTVAmbientAir:5.3litrespretrappeddesorbedwithTDAS2000ApplicationsThermaldesorptionisalong-knowntechnique,whichoffersawiderangeofapplications.MostcommonapplicationsincludegasanalyseswithadsorptionmaterialslikeTenaxorCarbotrap.Foryourconvenience,youcanpurchasepackedtubeswithanykindoftrappingmaterialfromSupelco.Otherapplicationsincludetheanalysisofsolids,whichisanextremelysensitivetechnique.Typicalthermaldesorptionapplicationsinvolvefoodflavor,plasticenvironmentalsamples.Anymaterialcanbepackedintothesampleglasstube.Theuseofaclosedcontainerensuresthatanyanalyteswillstaywithintheglasstube.Moreover,itiseasytotakefieldsamplesanalyzetheminyourlaboratoryatalatertime.