摘要
介绍一种三聚甲醛挥发经过转换器加热裂解得到甲醛的新方法,通过补充适量的平衡气进行稀释,采用称量法制备得到目标浓度的高压瓶装甲醛气体标准物质。实验表明(210±5)°C为最佳的裂解温度,采用气相色谱质谱联用的方法对裂解产物进行分析,甲醛的纯度为99.525%。使用经过内壁特殊处理的铝合金气瓶对研制的氮中甲醛气体标准物质进行存储,量值水平1~5μmol/mol,成功通过国家二级标准物质定级评审,标物编号为GBW(E)083617。将研制的4.92μmol/mol氮中甲醛气体标准物质,气瓶编号L55016195,送至英国国家物理研究院进行比对,测试结果为4.81μmol/mol,采用En值进行判定,比对结果为满意,也进一步验证称量法制备定值得到的瓶装甲醛气体标准物质的准确性。
A novel method for the preparation of formaldehyde from sublimate of trioxane followed by thermal conversion has been developed,filled by calculated balance gas for dilution,a high pressure cylinder gas standard of formaldehyde in nitrogen with gravimetric value has been prepared.The optimum temperature for decomposition was(210±5)°C and purity of formaldehyde was 99.525%by analyzing the conversion products using GC-MS.All mixtures were prepared in aluminum cylinders with passivation treated internally,this 1-5μmol/mol gas reference material has acquired the second class of national certified reference material GBW(E)083617.A gravimetric cylinder(L55016195)static standard of 4.92μmol/mol formaldehyde in a nitrogen matrix was produced and sent to NPL(National Physical Laboratory,UK)for an international comparison,the analysis value was 4.81μmol/mol,indicated a satisfied comparability confirmed by En number and a reliable accuracy of static gravimetric value.
作者
聂巍
周鑫
董了瑜
李志昂
郑力文
陈扬天
NIE Wei;ZHOU Xin;DONG Liaoyu;LI Zhiang;ZHENG Liwen;CHEN Yangtian(National Institute of Measurement and Testing Technology,Chengdu 610021,China)
出处
《中国测试》
CAS
北大核心
2020年第8期70-75,共6页
China Measurement & Test
基金
四川省科技服务业示范项目(2018GFW0187)。
关键词
甲醛
气体标准物质
称量法定值
国际比对
准确度
formaldehyde
gas reference material
gravimetric value
international comparison
accuracy
