液液萃取–气相色谱法测定地表水中硝基苯

采用液液萃取–气相色谱法测定地表水中硝基苯的含量。采用盐酸调节水样至pH值为4左右,在200mL水样中加入8 g氯化钠,以甲苯为萃取剂,以CD–5MS色谱柱进行分离,氢火焰离子化检测器检测地表水中硝基苯的含量。硝基苯的质量浓度在10~150μg/L范围内与色谱峰面积呈良好的线性关系,线性相关系数r=0.999 4,方法检出限为0.24μg/L。加标回收率在91.6%~96.7%之间,测定结果的相对标准偏差小于3(n=7)。该方法操作简便,灵敏度高,适用于地表水中硝基苯的分析。

Determination of Nitrobenzene in Surface Water by Liquid Liquid Extraction-Gas Chromatography

The method for detection of nitrobenzene in surface water by liquid liquid extraction-gas chromatography was established. Hydrochloric acid was adopted to adjust water pH to about 4, 8 g sodium chloride was added in the 200 mL water sample, toluene was used as extracting agent,CD-5MS chromatographic column was used for separation, the content of nitrobenzene in surface water was detected with hydrogen flame ionization detector. The concentration of nitrobenzene was linear with peak area in the range of 10-150μg/L with linear correlation coefficient of 0.9994. Detection limit of the method was 0.24μg/L. The standard addition recoveries ranged from 91.6% to 96.7%, the relative standard deviations of detection results were less than 3%(n=7). The method is simple to operate,which is suitable for the analysis of nitrobenzene in surface water with high sensitivity.