EDTA容量法测定铁矿石中的全铁的不确定度分析

Uncertainty Evaluation of Total Iron Content in Iron Ore by EDTA Volumetric Method

铁矿石中全铁含量是影响其性能的重要指标。文章依据企业标准Q/ZYWY1009-2008检测全铁含量,按照JJF1059-1999《测量不确定度评定与表示》[1]技术规范要求,对检测过程中的测量不确定度进行评定,分析了测量不确定度的来源,包括高纯铁标样纯度,摩尔质量,天平,容量瓶,移液管,滴定管,终点判定,重复测定的不确定度等。通过评定,当铁矿石中全铁含量为54.16%时,测量结果的扩展不确定度为0.34%。

The total iron content has an important influence on the properties of iron ore.It was determined by the enterprise standard Q/ZYWY1009-2008.The uncertainty of determination of total iron content in iron ore with EDTA volumetric method was evaluated based on the theory of assessing the degree of uncertainty of measurement in JJFl059-1999.The main sources of uncertainty were analyzed,including the uncertainty of the purity of high purity iron,moore quality,balance,volumetric flask,burette,pipette,end judge,measurement repeatability and so on.When the total iron content was 54.16 %,the expanded uncertainty was 0.34 %.