连续流动分析-分光光度法测定水和废水中总氮

对连续流动分析-分光光度法测定水和废水中总氮进行方法适用性验证，6家验证单位验证数据表明：方法在0 mg/L～10．0 mg/L范围内线性良好，相关系数为0．9996～0．9999；方法检出限为0．04 mg/L，测定下限为0．16 mg/L；6家实验室测定总氮标准溶液 RSD为0．4％～9．6％，测定总氮有证标准物质的结果在允许范围内，实际水样的加标回收率为92．0％～111％。该方法与国标方法同时测定多种类型的水样，结果无显著差异。探讨了影响该方法测定的干扰因素和消除方法，并提出方法应用要点。

Determination of Total Nitrogen in Water and Wastewater by Continuous Flow Analysis and Spectrophotometric Method

Applicability of continuous flow analysis and spectrophotometric method to measure total nitrogen in water and waste water was studied.Calibration results of 6 laboratories showed good linear regression in con-centration range between 0 mg/L and 10.0 mg/L with correlation coefficient varied from 0.999 6 to 0.999 9.The method detection limit was 0.04 mg/L and the quantitation limit was 0.16 mg/L.The test results of certified ref-erence material was in the permission range,RSD ranged from 0.4% to 9.6%.The recovery rate of real water samples was between 92.0%～111%.Therefore the aforesaid method shows no significant difference compared with national standard method.The interference factor and elimination method was discussed.