提高水中氨氮测定精准度的研究

Research on Improving the Measurement Precision of Ammonia Nitrogen in Water

纳氏试剂光度法是污水中氨氮测定广泛采用的方法,文章通过实验分析讨论实验室环境、水样预处理、酒石酸钾钠和显色温度、显色时间、pH值等实验条件对氨氮测定精准度的影响.实验结果表明：改善实验室环境,在20～25℃、显色15 min、显色后pH值为13的条件下,用滤膜代替滤纸,向酒石酸钾钠中加入NaOH煮沸浓缩定容能显著提高氨氮测定的精准度.

Nessler's reagent spectrophotometric method is widely used in the determination of ammonia nitrogen in wastewater.The impacts of laboratory environment,sample pretreatment,seignette salt and reaction temperature,reaction time and pH value on measurement precision were analyzed.The results elucidated that under the conditions of 20-25℃,reaction time of 15 min and pH of 13,the measurement precision of ammonia nitrogen determination was increased by filter membrane instead of filter paper.