摘要
为实现焦化企业周边地表水中多环芳烃(polycyclic aromatic hydrocarbons,PAHs)的检测,建立了液液萃取结合气相色谱-质谱法(GC-MS)测定16种PAHs残留的分析方法。通过优化色谱、质谱参数确定最佳分析条件,比较不同种类的提取剂(正己烷、二氯甲烷、二氯甲烷-正己烷混合液(V/V=1:1))及其用量、提取时间、提取次数对16种PAHs方法回收率的影响,确定最优前处理方法。取1 L水样加入20.0 g氯化钠,并用50 mL二氯甲烷提取两次,合并提取液并经无水硫酸钠脱水,定量浓缩至0.5 mL,再用二氯甲烷准确定容至1.0 mL。选用弱极性色谱柱HP-5 MS对目标物进行分离,在电子电离源(EI)模式和选择离子监测(SIM)模式下进行测定,氘代内标法定量。在最优提取条件下,16种PAHs可在37.0 min内完成色谱分离分析,在2~500μg·L^(-1)范围内线性关系良好,平均相对响应因子的相对标准偏差(RRF RSD)小于14%,方法检出限为0.003~0.01μg·L^(-1),定量限为0.02~0.04μg·L^(-1)。分别向实际水样添加3个不同质量浓度(0.01、0.05和0.25μg·L^(-1))水平进行回收试验,测得16种PAHs的平均回收率为63.0%~100.3%,相对标准偏差为0.7%~8.2%(n=6)。将该方法用于当地焦化企业周边地表水中16种PAHs残留筛查,结果显示受检的6份样品有3份不同程度检出7种PAHs单体,检出质量浓度(μg·L^(-1))较高的3种单体为苊(0.241)、芴(0.088)、荧蒽(0.075),∑_(16) PAHs总质量浓度范围为0~0.551μg·L^(-1)。研究建立的方法具有较高的选择性、正确度和灵敏度,可为调查焦化企业周边地表水中16种PAHs残留提供可靠的技术保障。
In order to achieve the detection of PAHs in surface water around coking enterprises,a method for the determination of16 PAHs by liquid-liquid extraction combined with gas chromatography-mass spectrometry was developed.Exactly speaking,the said method needs to optimize the instrument parameters and pretreatment conditions.To achieve the purpose,it is of course necessary to study the effects of gas chromatography mass spectrometry instrument parameters and different types of extractants,including n-hexane,dichloromethane,dichloromethane-n-hexane mixture(1:1,volume ratio) and its dosage,extraction time and extraction times on the recovery of 16 PAHs methods.The sample(1 L) was added with 20.0 g sodium chloride,and extracted twice with 50 mL dichloromethane,then the combined extract was dehydrated by anhydrous sodium sulfate,quantitatively concentrated to0.5 mL,and then accurately fixed to 1.0 mL with dichloromethane.The purified extract was separated by weak polar chromatographic column HP-5 MS,and determined in electron ionization source(El) mode and selective ion monitoring(SIM) mode,and quantified by deuterated internal standard method.The results showed that the 16 PAHs could be analyzed within 37 min.Under the optimized conditions,the calibration curves showed good linearities for 16 PAHs,and the relative deviation of the response factor being less than 14% in the range of 2 to 500 μg·L^(-1).Whereas the limits of detection and limits of quantification for 16PAHs under study should be within the range of 0.003 to 0.01 μg·L^(-1) and 0.02 to 0.04 μg·L^(-1),respectively.The recovery tests were carried out in the actual water samples at three spiked levels of 0.01,0.50,and 0.25 μg·L^(-1).The average recoveries of 16 PAHs were 63.0% to 100.3%,and the corresponding relative standard deviations(RSDs) were 0.7% to 8.2%(n=6).Apart from that,this method was successfully applied to the analysis of 16 PAHs residues in surface water around coking enterprises in Yuxi city.The results revealed the seven PAHs monomers
作者
刘淑娟
李国文
李元
叶正中
施艳峰
普学伟
李志林
LIU Shu-juan;LI Guo-wen;LI Yuan;YE Zheng-zhong;SHI Yan-feng;PU Xue-wei;LI Zhi-lin(College of Chemistry,Biology,and Environment,Yuxi Normal University,Yuxi 653100,China;College of AnimalScience and Technology,Yunnan Agricultural University,Kunming 650201,China;Ecological and Environmental Monitoring Station of DEEY in Yuxi,Yuxi 653100,China)
出处
《化学研究与应用》
CAS
北大核心
2024年第1期211-219,共9页
Chemical Research and Application
基金
中央水污染防治专项资金(云南省地下水基础环境状况调查评估,2110302水体)资助。
