8-羟基喹啉偶联光度法测定水中亚硝酸盐

DETERMINATION OF NITRITE IN WATER WITH SPECTROPHOTOMETRIC METHODS COUPLING 8-HYDROXY-QUINOLINE

用8-羟基喹啉偶联光度法测定水中亚硝酸盐。在室温下,亚硝酸盐和苯胺反应生成重氮盐,在碱性介质中(pH≥12.5),重氮盐与8-羟基喹啉偶联显色,其最大吸收波长为482nm。线性范围为0～3.56mg·L-1,标准偏差小于2.5%,检出下限为7.4μg·L-1。该方法方便、快速、灵敏,用于水样分析,结果满意。

The nitrite in water was determined by the spectrophotometric methods coupling 8hydroxyquinoline Nitrite and aniline reacted and formed diazonium at room temperature Diazonium and 8hydroxyquinoline coupled coloration in alkaline medium(pH>125, the maximum absorbing wavelength was 482nm Beer's law was valid in the range of 0～356 mg·L-1, RSD was less than 25%The limit of detection was below 74 μg·L-1 This method is convenient, rapid and sensitive, and the result of determination used in water sample is satisfied