紫外分光光度法和流动注射法测定水样中总氮的比对研究  

Comparison Experiment of UV Spectrophotometric Method and Flow Injection Analysis for Determination of Total Nitrogen in Water Samples

作　　者：夏汝丞 Xia Rucheng(Zhuhai Western Ecological Environment Monitoring Center,Zhuhai 519090,China)

机构地区：[1]珠海市西部生态环境监测中心,广东珠海519090

出　　处：《广东化工》2024年第20期174-176,187,共4页Guangdong Chemical Industry

摘　　要：针对实际样品总氮的测定,于实验室内对采用流动注射法代替紫外分光光度法进行测定的可靠性进行评估。分为两个实验:两种方法的质量控制实验与两种方法的比对实验。对于质量控制实验,测定结果均符合标准方法质控要求:曲线相关系数R≥0.999;计算检出限与计算测定下限分别小于方法检出限与测定下限;空白值、重复多次测定的相对标准偏差、加标回收率、有证标准样品测定均符合方法与证书要求。对于方法比对实验,采用两种方法对22组工业废水进行总氮测定,对其差异性进行t检验评估,其p值为0.054(大于0.05)。证明采用两种方法进行总氮测定无显著性差异,采用流动注射法代替紫外分光光度法是可靠的。此外,对影响总氮测定结果的可能因素(试剂品质与纯度、流动注射系统、pH、金属离子与非金属离子)也进行了探讨,得出干扰因素对此次实验的总氮测定影响较小的结论。This article focuses on the determination of total nitrogen in practical water samples,and evaluates the reliability of applying the flow injection analysis method to replace the UV spectrophotometric method in the laboratory.Specifically,two experiments are designed to achieve this gold:the quality control experiment and the comparison experiment of the two methods.For quality control experiments,the determination results of total nitrogen meet the quality control requirements of the standards:curve correlation coefficient R≥0.999;calculated detection limit and calculated lower limit of determination show a lower value than that in related standards;blank experiments,RSD for parallel determinations,recovery rates,and the determination of certified reference materials all meet the requirements of the standards or certificates.For the method comparison experiment,two methods were used to measure total nitrogen in 22 groups of industrial wastewater,and the difference was evaluated by t test.The p value was 0.054(over 0.05),which proved that the results for total nitrogen determination were not different to some extent when using two methods.Therefore,it is reliable to use flow injection method to replace UV spectrophotometric method.In addition,this article discusses potential factors(reagent quality and purity,flow injection system,pH,metal ions and non-metal ions)that affect the determination of total nitrogen,and concludes that interference factors have little impact on the determination of total nitrogen in this experiment.

关 键 词：总氮 流动注射 碱性过硫酸钾消解紫外分光光度 质量控制 比对实验 

分 类 号：O657.32[理学—分析化学]