还原-偶氮光度法测定水中硝基苯优化测定条件研究

对还原-偶氮分光光度法测定水中硝基苯类实验装置进行改革,研究并建立了分析测定的优化实验条件。在此实验条件的基础上,对测定方法中的显色酸度、样品空白等测定条件进行了优化和补充;增加了苯胺类样品空白实验,解决了苯胺类样品及空白样品与体系酸度调节条件不一致的问题;同时拓宽了校准曲线的测定范围。硝基苯质量浓度在0~1.6 mg/L范围内线性关系良好,方法检出限为0.004 mg/L。用优化改进后的测定方法对水质硝基苯标准样品和实际废水样品进行分析测定,样品测定精密度(n=6)小于3%;加标实验回收率达到96.4%~101.8%。

Study on the reduction-azo photometric method for the optimization of determination conditions of nitrobenzene in water

The experimental apparatus for the determination of nitrobenzene in water has been improved by reduction-azo photometric method,and the optimization conditions for analysis and determination have been studied and established. Based on this,the determination conditions,such as color acidity,sample blank,etc. in the determina-tion methods are optimized and supplemented. In addition,the blank tests of aniline samples are added,and,as a result,the problem of inconsistency in acidity adjustment conditions between aniline samples and blank samples is solved. Meanwhile,the determination range of calibration curve is expanded. The linear relationship is good,when the nitrobenzene concentration is in the range of 0-1.6 mg/L ,and the detection limit of this method is 0.004 mg/L. The optimized determination method is used for the analysis and determination of water quality of nitrobenzene standard samples and real wastewater samples. The precision of the method (n=6) is less than 3.0%. The recovery rate of standard tests reaches 96.4%-101.8%.