乙酰苯胺元素含量标准物质的研制  

Development of Certified Reference Material of Acetanilide for Elemental Content

作　　者：王海峰[1] 李佳[1] 孙国华[1] WANG Hai-feng;LI Jia;SUN Guo-hua(National institute of metrology of China,Beijing 100029,China)

机构地区：[1]中国计量科学研究院,北京100029

出　　处：《化学试剂》2022年第5期767-772,共6页Chemical Reagents

基　　金：国家市场监督管理总局科技计划项目(2021MK150);能力提升项目(31-ANL1814)。

摘　　要：有机元素分析仪用于测定有机化合物、煤炭等能源产品以及食品的碳、氢和氮元素含量,仪器需要有机纯物质元素含量标准物质来校准。研制了乙酰苯胺元素含量标准物质,编号为GBW06203。使用区域熔融装置提纯乙酰苯胺原料,然后分装制成标物候选物。采用气相色谱-质谱法和差示扫描量热法测定其有机杂质含量,采用卡尔·费休库仑法测量其水分,采用灼烧残渣称重法测量其无机杂质含量,然后根据质量平衡原理计算主组分的含量。然后根据主组分和杂质的含量及其分子中待测元素的含量,计算得到标准物质的碳、氢和氮元素含量标准值。标准值溯源至纯物质的质量、温度和原子量上。碳、氢和氮元素含量的标准值分别为71.087%、6.712%和10.363%,不确定度(U,k=2)分别为0.003%、0.002%和0.001%。标准物质的准确度达到了国际先进的水平。标准物质可用于杜马斯法等有机元素分析仪的校准,也可用于油品氮含量标准物质的配制,保障有机元素含量的量值准确。Organic elemental analyzer was used to determine the content of carbon,hydrogen and nitrogen of organic compounds,energy products,such as coal,and food.The analyzer should be calibrated by using the certified reference material(CRM)of organic pure substance for elemental content.The CRM of acetanilide for elemental content labelled as GBW06203 was developed.The raw acetanilide was purified by zone melting and then packaged as candidates of CRM.Gas chromatography-mass spectrometry(GC-MS)and differential scanning calorimetry(DSC)were used to determine the organic impurities content.Karl Fischer coulometric titration and the residue on ignition was used to determine the water content and inorganic impurities content,respectively.Then,the main component content was calculated based on the mass balance theory.The certified value of carbon,hydrogen and nitrogen content was calculated by using the individual component content and the aimed elemental content in its molecule.The certified value is traceable to the mass of pure substance,temperature,and atomic weight.The certified content of carbon,hydrogen and nitrogen was 71.087%,6.712%and 10.363%,respectively,with the uncertainty(U,k=2)of 0.003%,0.002%and 0.001%,respectively.The accuracy of CRM is on the advanced world level.The CRM can be used to calibrate the Dumas type organic elemental analyzer and prepare the CRM of petroleum for nitrogen content,which is helpful for the accuracy of the organic elemental content.

关 键 词：碳 氢 氮 元素分析 标准物质 

分 类 号：O657.6[理学—分析化学]