流动注射催化光度法测定环境水样中的痕量亚硝酸根

Determination of Trace Nitrite in Environmental Water by Flow-injection Catalytic Spectrophotometry

基于在pH为2.7的一氯乙酸缓冲溶液中亚硝酸根对溴酸钾氧化亮绿具有催化作用,建立了测定环境水样中痕量亚硝酸根的流动注射催化光度法。在室温下,当溴酸钾浓度为0.15mol/L、亮绿溶液浓度为1.12×10-3mol/L时,该方法的线性范围为0.04～0.36mg/L,检出限为7.44×10-4mg/L,测定频率为60次/h,相对标准偏差为1.1%(n=11)。

Based on the catalysis of nitrite on oxidation of brilliant green by potassium bromate in a buffer solution of chloroacetic acid with pH 2.7, a new flow-injection catalytic spectrophotometric method was founded for the determination of trace nitrite in environmental water sample. The experimental results show that when the determination is carried out at room temperature and the concentration of KBrO3 and brilliant green is 0. 15 mol/L and 1. 12 × 10^-3 mol/L respectively, the linear range for the method is 0.04-0.36 mg/L, and the detection limit is 7.44 × 10^-4 mg/L. The sampling frequency is about 60 time/h, and the relative standard deviation is 1.1% （ n = 11 ）.