反相流动注射催化光度法测定废水中的亚硝酸根

摘要

采用反相流动注射技术与催化光度法相结合，用微机化流动注射分析仪准确控制反应时间，优化了实验条件，克服了催化光度法反应时间难以控制引起的方法精密度、准确度不高的弱点，拟定了测定痕量亚硝酸根的流动注射催化光度方法。分析速度每小时20次，NO-2质量浓度在0.00～2.00 mg/L，回归方程斜率为0.155。方法直接测定电厂废水中NO-2 的结果与 Griess 法相符合，RSD<5.0 %（n=5）。%A method for the determination of nitrite in waste water by catalytic spectrophotometry with reversion phase flow injection system was developed. Computerized reversion phase flow injection system precisely controlled the reaction time and optimized the experimental conditions. The accuracy and precision for the determination of nitrite was improved remarkably. The linear range for nitrite was 0.00～2.00 mg/L. The sample throughput of the method was 20/h. The method has been applied to the determination of trace nitrite in the waste water from power plant. The results are in agreement with those from Griess method with precision of less than 5.0% RSD (n=5).