纳氏试剂光度法测定水和废水中氨氮方法的改进

对纳氏试剂光度法进行了改进，水样取样量改为10ml，在不改变反映体系pH值的前提下，纳氏试剂的用量改为0．10ml。改进法的校准曲线相关数γ〉0．999，最低检出限0．03mg／L，显色体系在90min内稳定，RSD〈5％，加标回收率为91．6％～104％。通过地下水、地表水、生活污水和工业废水的比对实验表明，改进法与标准法的测定结果无显著性差异。

水质 氨氮的测定 纳氏试剂分光光度法(HJ 535-2009)中滤纸的预处理方法的研究

该方法用絮凝沉淀法预处理样品的滤纸本身会残留部分氨,滤纸经不合适方法预处理,会带入分析过程中。本研究项目就是选用适当的方法对滤纸进行预处理,去除残留的氨。减少样品分析过程中因滤纸问题引起的偏差,提高了该方法的准确度。

Comparison of Three Methods for Determination of Ammonia Nitrogen in Surface Water

Nessler's reagent spectrophotometry,gas phase molecular absorption spectrometry and ion chromatography were respectively used to determine ammonia nitrogen in surface water.The detection limit,precision,accuracy and recovery rate of the three methods were compared,and the determination results of the actual water samples were analyzed by t test.The results showed that the three methods all could meet the requirement of the laboratory quality control,and there was no significant difference in the determination results.Compared with Nessler's reagent spectrophotometry,the operation of gas phase molecular absorption spectrometry and ion chromatography operation was more convenient and fast and has no pollution,which can be used for the determination of ammonia nitrogen content in a large quantity of surface water samples.