在线柱前还原-高效液相色谱-荧光检测器法测定地表水中3-硝基酚和4-硝基酚的含量  

Determination of 3-Nitrophenol and 4-Nitrophenol in Surface Water by High Performance Liquid Chromatography Combined with Fluorescence Detector after Online pre-Column Reduction

作　　者：郑振浩 吴述超 丁思远 王钦昊 许俊凯 孙朝阳 ZHENG Zhenhao;WU Shuchao;DING Siyuan;WANG Qinhao;XU Junkai;SUN Chaoyang(Ningbo Agricultural Technology Promotion Station,Ningbo 315012,China;Zhejiang Geology and Mineral Technology Co.,Ltd.,Hangzhou 311305,China)

机构地区：[1]宁波市农业技术推广总站,宁波315012 [2]浙江省地矿科技有限公司,杭州311305

出　　处：《理化检验（化学分册）》2024年第9期927-931,共5页Physical Testing and Chemical Analysis(Part B:Chemical Analysis)

基　　金：浙江省自然科学基金项目(LQY18B050001);宁波市公益性科技计划项目(2021S022)。

摘　　要：提出了在线柱前还原-高效液相色谱-荧光检测器法测定地表水中3-硝基酚和4-硝基酚含量的方法。取500 mL水样于分液漏斗中,加入30 g氯化钠,用10%(质量分数)盐酸溶液调节水样pH至小于2。加入40 mL体积比1∶1的二氯甲烷-乙酸乙酯混合溶液,振荡5 min,静置,收集有机相,重复萃取3次,合并有机相,用无水硫酸钠脱水,收集萃取液。在79 kPa下,于40℃旋转蒸发至干,用甲醇复溶并定容至1.0 mL。将装有填料粒径为70μm的锌粉还原柱与Hypersil GOLD色谱柱相连,以含0.39 g·L^(-1)乙酸、0.53 g·L^(-1)乙酸锌、0.083 g·L^(-1)硫酸铜的甲醇溶液为流动相进行分离,荧光检测器测定3-硝基酚和4-硝基酚的还原产物。结果表明:3-硝基酚和4-硝基酚的质量浓度在10~100μg·L^(-1)内与对应的还原产物峰面积呈线性关系,检出限(3S/N)分别为3.0,1.5μg·L^(-1);按照标准加入法进行回收试验,回收率为80.0%~92.6%,测定值的相对标准偏差(n=6)均不大于11%。A method for determination of 3-nitrophenol and 4-nitrophenol in surface water by high performance liquid chromatography combined with fluorescence detector after online pre-column reduction was proposed.500 mL of water sample was placed into a separating funnel,and 30 g of sodium chloride was added.The pH of the mixture was adjusted to less than 2 with 10%(mass fraction) hydrochloric acid solution.40 mL of a mixture of dichloromethane and ethyl acetate at a volume ratio of 1∶1was added,the mixture was shaken for 5 min and then settled,and the organic phase was collected,which was extracted repeatly 3 times.The organic phases were combined,and dehydrated with anhydrous sodium sulfate.The extract was collected,and rotary evaporated to near dryness at 40 ℃ under 79 kPa.The residue was re-dissolved and made its volume up to 1.0 mL with methanol.Hypersil GOLD chromatography column was connected with a zinc powder reduction column of packing particle size of 70 μm,and methanol solution containing 0.39 g · L^(-1) acetic acid,0.53 g · L^(-1 )zinc acetate,and 0.083 g · L^(-1) copper sulfate was used as mobile phase for separation.The reduction products of 3-nitrophenol and 4-nitrophenol were determined by fluorescence detector.As shown by the results,linear relationships between the peak areas of the corresponding reduction products and mass concentrations of 3-nitrophenol and 4-nitrophenol were found within 10-100 μg · L^(-1),with detection limits(3S/N) of 3.0,1.5 μg · L^(-1),respectively.Test for recovery was made by the standard addition method,giving results in the range of 80.0%-92.6%,with RSDs(n=6)of the determined values not more than 11%.

关 键 词：高效液相色谱法 荧光检测器 在线柱前还原 硝基酚 

分 类 号：O657.7[理学—分析化学]