电解质分析仪用标准物质原料纯度定值研究

Study on Certification of Purity in Reference Materials used for Electrolyte Analyzers

对制备电解质分析仪用溶液标准物质的3种高纯试剂原料无水醋酸钠、氯化锂、氯化钙的纯度进行定值研究。采用经检定/校准后的电感耦合等离子体质谱仪、电感耦合等离子体发射光谱仪、氧氮氢分析仪、碳硫分析仪、离子色谱仪对原料中所包含的无机杂质进行测定,采用干燥减量法对原料中所含的挥发性组分与水分含量进行测定,最后采用杂质扣除法对3种高纯试剂原料的纯度进行定值,通过对每种分析方法引入的不确定度进行分析评定,得到原料纯度的不确定度评定结果,取包含因子k=2,置信概率为95%,无水醋酸钠的纯度为(99.956±0.038)%、氯化锂的纯度为(99.933±0.054)%、氯化钙的纯度为(99.941±0.048)%,以上纯度定值结果可用于电解质分析仪用溶液标准物质及相关试剂溶液的制备。

The purity of anhydrous sodium acetate,lithium chloride,and calcium chloride in solution reference for the electrolyte analyzer was determined.The certified/calibrated inductively coupled plasma mass spectrometer,inductively coupled plasma atomic emission spectrometer,oxygen nitrogen hydrogen analyzer,carbon sulfur analyzer,and ion chromatograph were used to determine the inorganic impurities,and the drying decrement method was used to determine volatile components and water content in raw materials.Finally,the impurity deduction method was used to determine the purity of three high-purity reagents.The uncertainty evaluation results of the purity of raw materials were obtained by evaluating the uncertainty of each analysis method.The inclusion factor k=2,the confidence probability was 95%,the purity of anhydrous sodium acetate was(99.956±0.038)%,the purity of lithium chloride was(99.933±0.054)%,and the purity of calcium chloride was(99.941±0.048)%.The above purity calibration results can be directly used for the preparation of solution references for electrolyte analyzer and related reagent solutions.