油品氮含量标准物质的研制

Development of Reference Materials for Nitrogen Content of Petroleum Products

化学发光法定氮仪需要使用油品氮含量标准物质校准,以实现量值溯源。介绍了6种中低浓度的油品氮含量标准物质的研制过程,该系列标准物质采用国际上认可的重量法配制和定值,标准物质的特性量值(氮浓度)溯源至质量和体积等SI单位以及有机纯物质元素含量标准物质上,其均匀性和稳定性符合要求。标准物质的氮浓度标准值分别为2.04 mg/L、5.03 mg/L、9.91 mg/L、19.6 mg/L、50.3 mg/L和100.7mg/L,扩展不确定度U(k=2)分别为0.08 mg/L、0.10 mg/L、0.16 mg/L、0.5 mg/L、0.9 mg/L和1.2mg/L。该系列标准物质的研制过程符合标准物质研制规范,不确定度达到了国内同类标准物质的相同水平,适用于化学发光法定氮仪的检定和校准,有利于保障油品氮含量的量值准确可靠。

The chemiluminescence nitrogen meter needs to be calibrated with the standard material of nitrogen content in petroleum to realize the traceability of the quantity value. In the present study, the development of six Certified Reference Materials(CRMs) for petroleum with nitrogen content ranging from low to middle were described. This series of CRMs were prepared and certified by the internationally recognized gravimetric method, and the certified value, nitrogen content,was traceable to SI unit of mass and volume, as well as to the pure organic substance CRM for elemental content. The homogeneity and stability of CRMs were technically qualified. The certified nitrogen concentrations of this series of CRMs were 2.04 mg/L, 5.03 mg/L, 9.91 mg/L, 19.6 mg/L, 50.3 mg/L, and 100.7 mg/L, with corresponding uncertainty U(k=2)of 0.08 mg/L, 0.10 mg/L, 0.16 mg/L, 0.5 mg/L, 0.9 mg/L, and 1.2 mg/L, respectively. The development process of this series of reference materials conforms to relative standards, and the uncertainty has reached the same level as that of similar reference materials in China. It is suitable for the verification and calibration of chemiluminescence nitrogen meters and is conducive to ensuring the accuracy and reliability of the nitrogen content of petroleum products.