不同条件对纳氏试剂法测定水中氨氮含量的影响

Discussion on the influence of different conditions on determination nitrogen in water by Nessler's reagent

目的探索水质中氨氮测定的最佳条件。方法通过对实验用水质量、pH值、显色时间和显色温度等4个因素对氨氮测定结果影响进行论证。结果采用无氨水或超纯水在pH值为8-10,显色时间大于10 min、显色温度为20-30℃的条件下,水中氨氮的测定结果准确度高。结论最佳的实验条件对水中氨氮的测定结果具有较高的重复性和准确性,能有效提升水质中氨氮测定的准确度。

Objective To explore the best condition for the determination of ammonia nitrogen in water.Methods The influence of four factors,including the quality of experimental water,pH value,color development time and color development temperature,on the determination results of ammonia nitrogen is demonstrated.Results Under the conditions of ammonia-free water or ultrapure water,pH value 8-10,color developing time more than 10 min and color developing temperature 20-30℃,the determination accuracy of ammonia nitrogen in water is high.Conclusion The best experimental conditions have high repeatability and accuracy for the determination of ammonia-nitrogen in water,which can effectively improve the accuracy of the determination of ammonia-nitrogen in water.