邻苯胺基苯甲酸褪色光度法测定水中的苯胺

Determination of Aniline in Water by Discoloration Spectrophotometry of N-Phenylanthranilic Acid

在硫酸介质中，邻苯胺基苯甲酸被重铬酸钾氧化成紫红色物质，再加入苯胺，溶液颜色发生明显的变浅褪色现象，且吸光值会随之下降，在一定范围内其下降的程度与苯胺的含量呈线性关系，依此建立了邻苯胺基苯甲酸褪色分光光度测定苯胺类物质的方法。该法的最大吸收波长为510nm，表观摩尔吸光系数为1．2×10^4L·mol^-1cm^-1，苯胺浓度在20～60mg／L范围内符合比尔定律，用于水中苯胺物质的测定，其回收率在95．5％～108％之间，样品测定的相对标准偏差为0．82％～2．24％。

In the medium of Sulfuric Acid , N - Phenylanthranilic acid is oxygened. Based on this, a new photometric method for the determination of aniline is proposed. The absorptive maximum is at 510 nm with an apparent molar absorption of 1.2×10^4L— mol^-1 cm^-1, Beer＇s law is obeyed in the concentration range from 20 - 60mg/L. It is used for the determination of aniline in water. The recovery of the method is between 95.5% and 108% ,the precision is between 0. 82% and 2.24%.