氮中1,1,1,2-四氟乙烷气体标准物质的研制

Preparation of Gas Reference Material of 1,1,1,2-Tetrafluoroethane in Nitrogen

以高纯1,1,1,2-四氟乙烷和高纯氮气为原料,采用称量法制备100~1000μmol/mol氮中1,1,1,2-四氟乙烷气体标准物质。实验考察了机械混匀效果、钢瓶压力变化均匀性以及储存时间稳定性,并采用与被定值的物质摩尔分数相近的同类型国家一级气体标准物质(GBW06321)进行比对定值以及进行不确定度分析。结果表明,研制的气体标准物质标准值为100~1000μmol/mol,相对扩展不确定度为2%(k=2),有效期为12个月,具有良好的稳定性和均匀性,可进一步应用于制冷剂、环保等相关行业的仪器标定和检测。

Using high purity 1,1,1,2-tetrafluoroethane and high purity nitrogen gas as raw materials,100~1000μmol/mol 1,1,1,2-tetrafluoroethane gas reference material in nitrogen was prepared by gravimetric method. The mechanical mixing effect of the gas reference material, the uniformity of pressure change of the cylinder and the stability of storage time were investigated. And it was compared with the same type national gas reference material(GBW06321) with a similar mole fraction under the same conditions, the concentration of 1,1,1,2-tetrafluoroethane in nitrogen was determined. An uncertainty analysis was also carried out. The results showed that the gas reference material had good uniformity and stability. The concentration range of 1,1,1,2-tetrafluoroethane in nitrogen was100~1000 μmol/mol,the relative expanded uncertainty was 2%(k=2), the validity period was one year. The1,1,1,2-tetrafluoroethane gas reference material in nitrogen can be further applied in instrument calibration in related industries such as refrigerants and environmental protection.