凯氏定氮仪的发展史.ppt

July05/KJ,China_KjeldahlSolutions,1,凯氏定氮一个使用了120年的依旧年轻的技术,BCHILabortechnikAGKatharinaJehleFlawil,Switzerland,July05/KJ,China_KjeldahlSolutions,2,主题：,蛋白的基本概念凯氏定氮的方法方法的发展Bchis消化单元Bchis消化单元Kjeldahl法问题解决,July05/KJ,China_KjeldahlSolutions,3,蛋白的基本概念BasicsProtein,July05/KJ,China_KjeldahlSolutions,4,为什么要分析蛋白?蛋白质是：,Basicnutrient基本的营养Impactoncaloricvalue(17kJresp.4kcal)热量来源Parameterforquality(e.g.meat)品质参数Influenceonproductionprocess(e.ggelation,extrusion)影响产品的中间处理（例，冻结，压榨）Influenceonflavourandcolouroffood(e.g.bakingprocessbread,roastingprocesscoffee)影响食品的风味和颜色,July05/KJ,China_KjeldahlSolutions,5,蛋白的基本结构是氨基酸，分子式如下：,Thereareabout200aminoacidsfoundinnature自然界已发现的大概有200种氨基酸Thereareabout20aminoacidsinaproteinhydrolysate蛋白水解后大概有20种氨基酸,BasicsProtein,July05/KJ,China_KjeldahlSolutions,6,怎么测定蛋白质？通过检测氮的含量计算蛋白含量,Thenitrogencontentinproteinisinasmallrange(15%-18%,mean:16%)蛋白中氮的含量在1518波动，平均16Proteinisdeterminedbyanalysingthenitrogencontentandcalculatingtheprotein通过氮含量计算蛋白含量,BasicsProtein,July05/KJ,China_KjeldahlSolutions,7,凯氏定氮概述,July05/KJ,China_KjeldahlSolutions,8,谁是凯氏?,JohanKjeldahl184919001849borninDenmarkgraduationfromuniversityScientistatCarlsbergBreweries,FermentationstudiesDevelopmentofamethodforexactdetermi-nationofnitrogeninanimalandvegetablematerialResearchoncarbohydratesinbarleyandmalt,1883PublicationoftheKjeldahlmethod,July05/KJ,China_KjeldahlSolutions,9,凯氏定氮的原理,1.Digestion消化ConversionofProtein-NitrogentoNH4+将蛋白中氮转化为NH4+,2.Distillation蒸馏分离收集NH3SeparationofNH3,3.Titration滴定用酸中和滴定MeasureoftheAmountofAcidthatwasneutralisedbyNH3,July05/KJ,China_KjeldahlSolutions,10,Digestion消化(I),Blank,Sample,1.072,2tabsofCatalyst,Sulphuricacid,Weighsample称重1gofdryorganicmaterial(homogeneous)1克干的有机物质（均质）,SampleBlank空白addeverythingexceptsample,Addreagents加试剂10gor2tabsofKjeldahlcatalystmixture10g或2片凯氏消化片20ml硫酸,样品均质，称重后加入试剂,July05/KJ,China_KjeldahlSolutions,11,Digestion消化(II),vapourstoScrubber,Digestiondigestat370Cfor90minoruntilthemixtureisclear(green/bluecolor)+30min37090mins或消化澄清后30分钟,Digestion,July05/KJ,China_KjeldahlSolutions,12,Distillation蒸馏(I),manually,orautomated,Dilutiondilutethecooleddigestionsolutionwith50mldeionisedwater加入50ml去离子水稀释,Dilution稀释,July05/KJ,China_KjeldahlSolutions,13,Distillation蒸馏(II),PreparationofReceiver准备接受液,July05/KJ,China_KjeldahlSolutions,14,Distillation蒸馏(III),SodiumhydroxideNaOHadd90mlofNaOH32%tothediluteddigestionsolution加90ml32的NaOH到溶液中,Distillation蒸馏distillfor4min.蒸馏4分钟,NeutralisationandDistillation,July05/KJ,China_KjeldahlSolutions,15,Titration滴定,Boricacidtitration硼酸滴定titratethecondensatewithsulphuricacidstandardsolution(0.5Norequivalent)totheendpointofpH4.65用0.5N的硫酸标准液中和滴定至终点PH4.65Backtitration反滴定titratethecondensatewithsodiumhydroxidestandardsolution(0.5Norequivalent)用0.5N的NaOH标准液中和滴定,Titration,July05/KJ,China_KjeldahlSolutions,16,Calculation计算,1.4007:1ml0.1NVolumetricSolution1.4007mgNN:NormalityAcidPF:ProteinfactorNProtein,July05/KJ,China_KjeldahlSolutions,17,ProteinFactors蛋白转换因子,SampletypeProteinFactorGelatine5.55Dairyproducts6.38Meat6.25Fish6.25Nuts,oilseeds5.4Cereals6.25Fruit,Vegetable6.25Corn6.25Eggs6.25,July05/KJ,China_KjeldahlSolutions,18,凯氏定氮法的发展,July05/KJ,China_KjeldahlSolutions,19,最早,July05/KJ,China_KjeldahlSolutions,20,Buchi公司开始凯氏分析于：,1961开始生产上市凯氏定氮仪市场上第1个带有内置蒸汽发生器的蒸馏仪，大大提高蒸馏效率,July05/KJ,China_KjeldahlSolutions,21,定氮仪在Bchi的发展演变,July05/KJ,China_KjeldahlSolutions,22,Bchi今日,DigestionUnitsandScrubber消化单元和排废装置,DistillationUnits蒸馏单元,July05/KJ,China_KjeldahlSolutions,23,BchisDigestionUnits消化单元,July05/KJ,China_KjeldahlSolutions,24,消化加热方式,InfraredHeating红外加热,BlockHeating整体铝块加热,July05/KJ,China_KjeldahlSolutions,25,红外消化炉特点,红外加热，通过辐射方式，非接触式加热升温速度快（10min预热）可以升温至650C消化管排废和消化管紧密联接6管消化仪(K-424)或12管(K-435)加热步骤可控，定时器12管(K-435),K-424,K-435,July05/KJ,China_KjeldahlSolutions,26,整体铝块加热消化炉的特点,K-437,K-438,铝块加热-接触式加热可以升温到450C温度时间可控消化管排废和消化管紧密联接酸气回收装置可控20个消化位置自动提升(K-438only)K-438:程序化(时间延迟,升温梯度,自动停止,),July05/KJ,China_KjeldahlSolutions,27,Digestion,红外和整体铝块消化炉的区别,Block铝块IR红外预热时间60min5min温控Temperatureeasydifficultcontrol加热单元最大加热温度450C600C,July05/KJ,China_KjeldahlSolutions,28,Digestion,铝块Block红外IRWatersamples+upto100mlLiquidsamples+upto15mlDryorganicmaterial+0.2gto5gHumidorganicmaterial+0.2gto5gFoamysamples+Mineraloil+,DifferencesIRBlock红外和整体铝块消化炉的区别,July05/KJ,China_KjeldahlSolutions,29,如何处理消化过程中的酸雾？,Sulphuricacidvapoursarecorrosiveandvitriolic酸雾具有腐蚀性和毒性，解决方法：1)消化炉排废装置，标准配置2)中和酸雾的废气循环回收装置,July05/KJ,China_KjeldahlSolutions,30,ScrubberB-414,模块化设计,可达4步高效能泵系统,34l/min大的回收试剂腔,3l大的气液接触面积,提高操作性能可加NaOHor碳酸钠(最高NaOH20%但推荐浓度NaOH10%)可以选择抗酸，提供特殊密封垫（抗酸）吸收步骤使用活性炭吸附,July05/KJ,China_KjeldahlSolutions,31,Step1(optional)冷凝,Step2(standard)中和,Step3(standard)吸收,Step4(optional)反应,ScrubberB-414,July05/KJ,China_KjeldahlSolutions,32,消化炉特殊附件,Suctionmoduleforaqueoussamples水类样品吸收模块,带有冷凝漕的吸收模块，专门处理水类样品，防止交叉污染,用于H2O2消化的吸收模块(仅适用于K-424andK-435),用于连续添加H2O2的漏斗环保(不需要催化剂)更短的消化时间减少起沫,July05/KJ,China_KjeldahlSolutions,33,Refluxmodule回流模块(仅适用于K-424andK-435),适用于必须在回流状况下才能进行的消化ModuleforDigestionswhichhavetobedoneunderrefluxconditions,DigestionUnits:SpecialAccessory消化炉特殊附件,July05/KJ,China_KjeldahlSolutions,34,COD-Accessory化学耗氧量附件(仅适用于K-437andK-438),DeterminationoftheChemicalOxygenDemand,DigestionUnits:SpecialAccessory消化炉特殊附件,July05/KJ,China_KjeldahlSolutions,35,BchisDistillationUnits蒸馏单元,July05/KJ,China_KjeldahlSolutions,36,STEAM,July05/KJ,China_KjeldahlSolutions,37,老型号K-314,BasicinstrumentforKjeldahlandNitrogendeterminationDisadvantagesK-314notimeroldtechnologyprice-performanceratio,July05/KJ,China_KjeldahlSolutions,38,蒸馏单元K-350andK-355总介绍,DistillationUnitK-350K-314替代产品,DistillationUnitK-355凯氏定氮的延伸产品,July05/KJ,China_KjeldahlSolutions,39,K-350的特点,用于凯氏氮检测的基本型号定时器可存储一个方法:蒸馏时间和试剂量紧凑设计安全特点:消化管在位传感器,安全门以及维修门传感器,July05/KJ,China_KjeldahlSolutions,40,K-355的特点,具有K-350全部功能，另加：蒸汽输出量可调(30100%)额外配置抗强酸的泵(用于加强酸和水)冷凝水控制传感器可以储存9个程序:蒸馏时间,试剂量和蒸汽输出量不仅适用于凯氏定氮，还适用于更广泛的的应用,July05/KJ,China_KjeldahlSolutions,41,预算不高样品数量不多K-350:应用于KjeldahlandDevarda,K-350/K-355的目标客户,K-355:应用于Kjeldahl,Devarda和非凯氏应用在样品准备中需要蒸溜应用的,July05/KJ,China_KjeldahlSolutions,42,我们的口号“STEAM”,S安全操作,T节约时间和成本,E高效蒸馏,A官方认可的方法,M多用途设计,July05/KJ,China_KjeldahlSolutions,43,蒸馏单元B-324,内置滴定仪连接装置可以升级为全自动的蒸馏单元电子蒸汽调节内置泵系统用于NaOH,水和硼酸的添加消化管自动排空存储20种方法操作简单,LCD显示,July05/KJ,China_KjeldahlSolutions,44,B-324的目标客户,想要操作更舒适的想要连接滴定单元的客户应用于Kjeldahl,Devarda和steamdistillation蒸汽蒸馏的客户,July05/KJ,China_KjeldahlSolutions,45,蒸馏单元K-370,蒸馏和滴定全部内置于一台仪器带有彩色显示屏的大控制面板最新的软件设计，带有-方便的数据输入输出功能-多任务处理-多语言-高存贮性能10000数据-用户可以自定义方法紧密，功能型设计配备K-371自动进样器，可以实现自动进样,July05/KJ,China_KjeldahlSolutions,46,称量:自动样品量输入,精确的液体加样器:用于反滴定,自动型消化炉K-438:ControlandDocumentationofDigestionProcess,PC:数据转移和备份,自动进样器:多样品的自动处理,打印机:外接A4Printer支持PCL3,蒸馏单元K-370,July05/KJ,China_KjeldahlSolutions,47,自动进样器K-371,K-437&K-438的20管架子可以适合自动进样器特殊架子:4管ExpressRack样品通过K-370控制利用蒸汽实现样品的转移由样品架到蒸馏单元,July05/KJ,China_KjeldahlSolutions,48,自动进样器K-370/371,自动进样器K-371,蒸馏仪K-370,样品转移原理,July05/KJ,China_KjeldahlSolutions,49,自动进样器K-370/371,自动进样器K-371,蒸馏仪K-370,蒸馏过程中蒸汽的走向,July05/KJ,China_KjeldahlSolutions,50,自动进样系统K-370/371,回收率(NH4)H2PO4,July05/KJ,China_KjeldahlSolutions,51,CustomerswhowantmaximumcomfortCustomerswithhighsample通量(15样品/天)需要标准化处理的客户需要广泛认证的客户,K-370/371的目标客户,July05/KJ,China_KjeldahlSolutions,52,Lastbutnotleast,精确的接口制造用于和排废装置的紧密联接，有效防止烟雾泄漏专业的冷凝装置，避免飞溅和硫酸的过量消耗更宽的直径48mm=对起沫样品更有利300ml的大容量=可以消化大量的样品,48mm,GlassblowingoneofBchisKeyCompetences玻璃吹制Buchi公司核心竞争力之一,July05/KJ,China_KjeldahlSolutions,53,DistillationUnits:SpecialAccessory蒸馏单元的专业附件,Devarda防溅保护检测NO2-和NO3-必需的附件(例：肥料),July05/KJ,China_KjeldahlSolutions,54,TroubleShooting,July05/KJ,China_KjeldahlSolutions,55,仪器校验方法,Distillation蒸馏,标准物质磷酸二氢氨(无水）(NH4)H2PO4(waterfree)理论含量:12.17%,DigestionandDistillation消化和蒸馏,标准物质:甘氨酸Glycin(99.7%)理论含量:18.66%,July05/KJ,China_KjeldahlSolutions,56,TroubleShooting:结果太