吹扫捕集/气相色谱法测定土壤中甲基汞和乙基汞含量  

Determination of methyl mercury and ethyl mercury in soil by purge and trap/GC

作　　者：杜明月 杜洋 谢璇 黄岩 吴旸 DU Ming-yue;DU Yang;XIE Xuan;HUANG Yan;WU Yang(Ji'nan Ecology and Environment Monitoring Center of Shandong Province,Ji'nan 250102,China;Huludao Ecological Environment Protection Service Center,Huludao 125000,China)

机构地区：[1]山东省济南生态环境监测中心,山东济南250102 [2]葫芦岛市生态环境保障服务中心,辽宁葫芦岛125000

出　　处：《化学工程师》2025年第2期26-29,92,共5页Chemical Engineer

基　　金：2023年山东省生态环境污染防治资金项目(2023S92):济南市黄河流域水生态状况评估。

摘　　要：建立了吹扫捕集/气相色谱法测定土壤中甲基汞和乙基汞含量的方法。0.10g样品在80℃经25%碱消解液消解3.0h后得到消解液,加入醋酸-醋酸钠缓冲溶液调节pH值至4~6之间,加入40.0μL四丙基硼化钠衍生试剂,将样品中的甲基汞和乙基汞转化为易挥发的甲基丙基汞和乙基丙基汞,经吹扫捕集、热脱附,DB-1(15m×0.53mm×0.50μm)色谱柱上分离后,再高温裂解后用冷原子荧光光谱测定。结果表明,当样品量为0.1g、提取液为15.0mL时,甲基汞和乙基汞在5.0~800.0 pg浓度范围内具有良好的线性关系,且相关系数均大于0.9990,方法检出限均为0.15μg·kg^(-1),加标回收率为80.9%~102.8%,相对标准偏差均小于10%。该方法前处理操作简单,检出限低、耗时短、分离效果好、精密度好、准确度高,适用于土壤中甲基汞和乙基汞含量的测定。A method was established for the determination of methyl mercury and ethyl mercury in soil by purge and trap/GC.0.10g samples were digested with 25%alkaline digestion solution for 3.0h at 80℃to obtain the digestion solution,adjusting pH value between 4 and 6 by adding acetic acid-sodium acetate buffer solution,adding 40.0μL tetrapropyl sodium boride derived reagents to convert the methyl mercury and ethyl mercury into volatile methylpropyl mercury and ethyl propyl mercury with sodium tetrapropyl boride as derivatization reagent,separated by DB-1(15m×0.53mm×0.50μm)after puring traping and thermal desorption,pyrolyzed at high temperature and analyzed by cold atomic fluorescence spectrometry.The results showed that when the sample was 0.10g and the extract was 15.0mL,the methyl mercury and ethyl mercury were good fittin relationship in the range of 5.0~800.0pg,the correlation coefficients were greater than 0.9990,the detection limits were 0.15μg·kg^(-1),the recovery were 80.9%~102.8%,and the RSDs were less than 10%。The method is suitable for the determination of methyl mercury and ethyl mercury in soil with simple pre-treatment produce,low detection limit,time-consuming,good baseline separation,good precision,high accuracy.

关 键 词：碱消解 丙基化衍生 气相色谱法 土壤 甲基汞 乙基汞 

分 类 号：X831[环境科学与工程—环境工程]