微量亚硝酸盐分析方法的研究

碱性桃红T在pH=1的盐酸溶液中可与亚硝酸根生成红色配合物。该配合物在波长为600 nm处有最大吸收,表观摩尔吸光系数为7.38×103L/(mol.cm),亚硝酸盐质量浓度在0μg/mL~3μg/mL,遵守Beer定律,标准偏差1.15×10-3,相对标准偏差0.22%,回收率97%~101%。该法适用于泉水、湖水、河水、污水等水样中亚硝酸盐的分析。

A method for the determination of trace nitrite

The method for the determination of trace nitrite is based on the reaction of nitrite with Safranine T to form red colour complex with an absorption maximum at 600 nm.The apparent ε value at 600 nm is 7.38×10^3 L/（moL·cm）.Beers law is obeyed for 0 to 3 μg/mL of nitrite.The colour is stable for up to 6 hours at room temperature with a standard deviation of 1.15×10^-3 absorbance and the relative standard deviation of 0.22.The method is satisfactory for analyzing nitrite in waters.