項目六：鋼鐵分析任務二：鋼鐵中碳的測定鋼鐵中碳的測定課程：工業(yè)分析中文Scenario6:SteelanalysisTask2:DeterminationofcarboninsteelDeterminationofcarboninsteelCourse:IndustrialAnalysisEglish一、鋼鐵中碳的測定方法介紹碳的存在形式游離碳：不溶于酸化合碳：能溶于酸而破壞測定各種形態(tài)的碳屬于相分析；在成分分析中，一般鋼樣只測定總碳量。生鐵試樣除測定總碳量外，常分別測定游離碳和化合碳的含量。中文一、IntroductiontothedeterminationmethodofcarboninsteelTheexistenceformofcarbonFreecarbon:insolubleinacidsCompoundcarbon:candissolveinacidandbedestroyedTheoperationofmeasuringvariousformsofcarbonbelongstophaseanalysis;Incompositionanalysis,generallyonlythetotalcarboncontentismeasuredforsteelsamples.Inadditiontomeasuringthetotalcarboncontent,thecontentoffreecarbonandcombinedcarboninpigironsamplesisoftenmeasuredseparately.Eglish總碳量的測定方法有很多，但通常都是將試樣置于高溫氧氣流中燃燒，使之轉(zhuǎn)化為二氧化碳再用適當方法測定，具體又分為以下幾種：燃燒-氣體容量法燃燒-庫侖法燃燒-非水滴定法中文Therearemanymethodsformeasuringtotalcarboncontent,andthemostcommonlyusedmethodisusuallytoburnthesampleinahigh-temperatureoxygenflow,convertitintocarbondioxide,andthenuseappropriatemethodstomeasureit.Specifically,thereareseveraltypes:combustiongascapacitymethodcombustioncoulombmethodcombustionnonaqueoustitrationmethodEglish1、燃燒-氣體容量法燃燒-氣體容積法是目前國內(nèi)外廣泛采用的標準方法。本法成本低，有較高的準確度，測得結(jié)果是總碳量的絕對值。其缺點是要求有較熟練的操作技巧，分析時間較長，對低碳試樣測定誤差較大。中文1、CombustiongascapacitymethodThecombustiongasvolumemethodiscurrentlywidelyusedasastandardmethodbothdomesticallyandinternationally.Thismethodhaslowcostandhighaccuracy,andthemeasuredresultistheabsolutevalueoftotalcarboncontent.Itsdisadvantageisthatitrequiresproficientoperationalskills,longeranalysistime,andlargermeasurementerrorsforlow-carbonsamples.Measurementprocessstep1●Placethesampleinahigh-temperaturefurnaceandburnitafteroxygenisintroducedStep2ThegeneratedgascontainingCO2iscollectedinameasuringtubetomeasureitsvolume,andthenCO2isabsorbedbyKOHStep3MeasurethechangeingasvolumeinthemeasuringtubebeforeandafterabsorptionStep4CalculatetheresultsbasedonthetemperatureandpressureduringmeasurementEglish2、燃燒-庫侖法Ba(ClO4)2+CO2+H2OBaCO3+HClO4中文2、CombustioncoulombmethodBa(ClO4)2+CO2+H2OBaCO3+HClO4Measurementprocessstep1●Placethesampleinahigh-temperaturefurnaceandburnitafteroxygenisintroducedStep2ThegeneratedCO2isabsorbedbyaBa(ClO4)2solution,whichchangesthepHofthesolutionStep3ElectrolysisreturnsthepHofthesolutiontoitsinitialstateStep4CalculatecarboncontentbasedontheamountofelectricityconsumedbyelectrolysisEglish3、燃燒-非水滴定法中文3、CombustionnonaqueoustitrationmethodMeasurementprocessstep1step2step3Placethesampleinahigh-temperaturefurnaceandburnitafteroxygenisintroducedThegeneratedCO2isabsorbedbyanethanolethanolaminesolutionTitrationofabsorptionsolutionwithpotassiumethanolsolutionEglish二、燃燒-氣體容量法測定鋼鐵中碳1、方法原理試樣在1200～1300℃的高溫O2氣流中燃燒，鋼鐵中的碳被氧化生成CO2:C+O2=CO24Fe3C+13O2=4CO2+6Fe2O3

Mn3C+3O2=CO2+Mn3O3FeS+5O2=Fe3O4+3SO23MnS+5O2=Mn3O4+3SO2用KOH吸收CO2除硫劑：活性二氧化錳中文二、Determinationofcarboninsteelbycombustiongasvolumetricmethod1、Methodprinciple

ThesampleburnsinanO2airflowathightemperaturesrangingfrom1200to1300℃,andthecarboninthesteelisoxidizedtoproduceCO2:

C+O2=CO24Fe3C+13O2=4CO2+6Fe2O3

Mn3C+3O2=CO2+Mn3O3FeS+5O2=Fe3O4+3SO23MnS+5O2=Mn3O4+3SO2UsingKOHtoabsorbCO2Desulfurizationagent:activemanganesedioxideEglish圖

氣體容量法定碳裝置1-氧氣瓶，2-氧氣表，3-緩沖瓶，4、5-洗氣瓶，6-干燥塔，7-玻璃磨口塞，8-管式爐，9-燃燒管，10-除硫管，11-容量定碳儀(包括:冷凝管a、量氣管b、水準瓶c、吸收瓶d、小旋塞e、三通旋塞f），l2-球形干燥管，13-瓷舟，14-溫度自動控制器，15-供氧旋塞2、測定儀器中文GasCapacityCarbonizationDevice1-Oxygencylinder,2-Oxygenmeter,3-Buffercylinder,4,5-Washingcylinder,6-Dryingtower,7-Glassgrindingplug,8-Tubefurnace,9-Combustiontube,10-Sulfurremovaltube,11-Capacitycarbonanalyzer(includingcondensertubea,measuringtubeb,levelbottlec,absorptionbottled,smallcocke,three-waycockf),12-Sphericaldryingtube,13-Porcelainboat,14-Temperatureautomaticcontroller,15-Oxygensupplycock2、measuringinstrumentEglish3、測定試劑氫氧化鉀吸收劑溶液（400g/L）；除硫劑活性二氧化錳（粒狀）或釩酸銀；酸性氯化鈉溶液（250g/L）；助熔劑：錫粒（或錫片）、銅、氧化銅、純鐵粉；高錳酸鉀溶液（40g/L）；甲基橙指示劑（2g/L）。中文3、TestingreagentsPotassiumhydroxideabsorbentsolution(400g/L);Sulfurremovalagent:activemanganesedioxide(granular)orsilvervanadate;Acidicsodiumchloridesolution(250g/L);Fluxes:tinparticles(ortinsheets),copper,copperoxide,pureironpowder;Potassiumpermanganatesolution(40g/L);Methylorangeindicator(2g/L).Eglish4、測定步驟將爐溫升至1200～1350℃，檢查管路及活塞是否漏氣，裝置是否正常，燃燒標準樣品，檢查儀器及操作。稱取適量試樣置于瓷舟中，將適量助熔劑覆蓋于試樣上面，打開玻璃磨口塞，將瓷舟放入瓷管內(nèi)，用長鉤推至高溫處，立即塞緊磨口塞。預熱lmin，按照定碳儀操作規(guī)程操作，測定其讀數(shù)(體積或含量)。打開磨口塞，用長鉤將瓷舟拉出，即可進行下一試樣分析。中文4、Measurementsteps

Raisethefurnacetemperatureto1200-1350℃,checkforleaksinthepipelinesandpistons,ensurethedeviceisfunctioningproperly,burnstandardsamples,andinspectinstrumentsandoperations.

Weighanappropriateamountofsampleandplaceitinaporcelainboat.Coverthesamplewithanappropriateamountofflux,opentheglassgrindingplug,placetheporcelainboatintotheporcelaintube,usealonghook