碱性过硫酸钾消解-离子色谱法测定水质总氮

Water Quality Determination of Total Nitrogen Using Alkaline Potassium Persulfate Digestion-Ion Chromatography Method

使用国标方法GB/T 11894—89测定水质总氮过程中,过硫酸钾和氢氧化钠在220nm下对吸光度的有明显干扰。为了消除其影响,研究采用改进的碱性过硫酸钾消解法结合离子色谱法测定了水质总氮含量。结果表明,总氮校准曲线线性相关系数R达0.9992,并且能在很大范围内呈现线性。运用此方法实测标样和水样,精密度和准确度都能满足需求,表明该方法测定结果可靠,适于测定水中不同范围的总氮,因此具有一定的应用价值。

While using the GB /T 11894—89 method to determine the total nitrogen,potassium persulfate and sodium hydroxide were found to have significant interference in ultraviolet absorbency under 220nm.A new method which combines alkaline potassium persulfate digestion with ion chromatography was taken to determine the total nitrogen amount in order to eliminate the interference above.The result shows that the correlation coefficient R of the total nitrogen calibration curve is 0.9992,with a large range of linearity.The accuracy and preciseness of the method all meet the needs in standard and sample determination.The results indicate that this method is reliable and suitable for the determination of total nitrogen of different concentration range in water.Therefore it has its value in application.