离子选择性电极法测定污水处理厂进出水中的氨氮含量

摘要

建立了离子选择性电极法测定污水处理厂进出水中氨氮的方法,对氨氮含量在0.1 ～ 100 mg/L的水样进行了测定条件的研究.该方法标准曲线的线性相关系数为0.999 8～ 1.000,检出限为0.004 mg/L,加标回收率为96.2％～103.8％,相对标准偏差(RSD,n=6)在0.57％～ 1.62％.对比该方法与纳氏试剂比色法的检测结果发现,水样氨氮浓度大于0.5mg/L时,相对平均偏差小于5％;氨氮浓度小于0.5mg/L时,相对平均偏差小于10％.该方法无须对样品进行预处理、操作简单、灵敏度高、准确、重现性好,适用于大批量水样中氨氮的测定.%A method for determination of ammonia nitrogen in influent and effluent from wastewater treatment plants(WWTP) by ionselective electrode was established,and the measurement conditions were discussed for the concentration of ammonia nitrogen in the range of 0.1 ～ 100 mg/L in water samples.Linear correlation coefficients were between 0.999 8 ～ 1.000,detection limit found was 0.004 mg/L,recoveries found was 96.2％～ 103.8％,relative standard deviations (RSD,n =6) found was 0.57％ ～ 1.62％.Results between the electrode method and Nessler's reagent colorimetric method were contrasted in the analysis.When ammonia nitrogen concentration of the water samples was greater than 0.5 mg/L and less than 0.5 mg/L,relative average deviations found was less than 5 ％ and 10 ％,respectively.The method is simple,without pretreatment and has good accuracy,precision and reproducibility.It,s suitable for the determination of ammonia in a large number of water samples.