海水重金属监测分析方法比较研究

发布时间：2019-02-12 12:54

【摘要】：海水中重金属元素的监测一直备受关注。国家标准对于每种重金属元素的分析均给出了2-4种不同的分析方法。实际中,由于不同的实验室对于同一种元素的测定选择的分析方法不同,分析结果可能有所差别。这一现象降低了近岸海域海水调查数据的可比性,容易导致一些痕量元素海洋化学行为的研究困难,限制了污染水平评价的可靠性。本研究根据实际情况,以国家近岸海域环境监测网网络成员单位为调查对象,对海水重金属监测分析方法的实际应用情况进行了研究,主要包括两部分内容。首先调查了海水重金属监测分析方法的实际应用情况,然后通过对海水中总铬、铜、铅、镉、锌、汞元素不同分析方法进行比对实验,优选并推荐了适合实际应用的分析方法。 1.向近海网成员单位以调函形式发放了调查问卷。回收信息进行了整理、总结,得出了目前国内监测站海水重金属各分析方法的实际工作使用比例。同时,确定了下一步研究工作内容,对总铬、铜、铅、镉、锌、汞6种重金属元素进行方法比对实验。 2.比较了测定海水总铬的GF-AAS法和DPC法,旨在考察两方法的实验室实际应用情况。GF-AAS法和DPC法测定海水总铬的检出限分别为0.17μg/L、0.11μig/L,加标回收率分别为102.3%～103.5%、98.2%～101.6%,实验室内相对标准偏差分别为4.52%-5.42%、4.90%-5.31%。 3.比较了测定海水中铜、铅、镉的GF-AAS法和ASV法,旨在考察两方法的实验室实际应用情况。GF-AAS法和ASV法测定海水中铜的检出限分别为0.10μgL、2.33μg/L,加标回收率分别为101.5%～107.7%、87.2%～147.8%,实验室内相对标准偏差分别为4.56%～-6.59%、11.60%～19.41%。GF-AAS法和ASV法测定海水中铅的检出限分别为0.15μg/L,0.38μg/L,加标回收率分别为100.7%-101.0%、97.8%-143.2%,实验室内相对标准偏差分别为3.71%-8.56%、16.69%～18.72%。GF-AAS法和ASV法测定海水中镉的检出限分别为0.15μg/L,0.02μg/L,加标回收率分别为98.0%-98.8%、99.8%-107.1%,实验室内相对标准偏差分别为4.11%-5.02%、8.22%-8.71%。 4.比较了测定海水中锌的FAAS法和ASV法,旨在考察两方法的实验室实际应用情况。FAAS法和ASV法测定海水中锌的检出限分别为1.73μg/L,1.06μg/L,加标回收率分别为101.1%-103.7%、138.7%-145.9%,实验室内相对标准偏差分别为2.93%-3.12%、16.76%～17.11%。 5.比较了测定海水中汞的CAAS法和AFS法,旨在考察两方法的实验室实际应用情况。CAAS法和AFS法测定海水中汞的检出限分别为0.010μg/L、0.008μg/L,加标回收率分别为97.1%～97.2%、97.0%～99.2%,实验室内相对标准偏差分别为0.67%～0.99%、0.86%～1.92%。 6.依据实验数据,考虑检出限、方法准确度和精密度、前处理过程、方法繁复性等,推荐使用GF-AAS法测定海水中总铬、铜、铅、镉,使用FAAS法测定海水中锌,使用AFS法测定海水中汞。
[Abstract]:The monitoring of heavy metal elements in seawater has been paid more and more attention. The national standard gives 2-4 different analytical methods for each heavy metal element. In practice, the analytical results may differ due to the different analytical methods for the same element in different laboratories. This phenomenon reduces the comparability of the sea water survey data in the coastal waters and easily leads to the difficulty of studying the marine chemical behavior of some trace elements and limits the reliability of the assessment of the pollution level. According to the actual situation, this paper studies the application of the method of monitoring and analyzing heavy metals in sea water by taking the member units of the national environmental monitoring network in the coastal sea area as the objects of investigation, which mainly includes two parts. This paper first investigates the practical application of heavy metal monitoring and analysis methods in seawater, and then, by comparing the analytical methods of total chromium, copper, lead, cadmium, zinc and mercury in seawater, the analytical methods suitable for practical application are selected and recommended. 1. A questionnaire was distributed to the offshore network member units in the form of dispatch letters. The recovery information is sorted out and summarized, and the actual working proportion of each analysis method of sea water heavy metals in domestic monitoring station is obtained. At the same time, the contents of the next research work were determined, and the comparison experiments of total chromium, copper, lead, cadmium, zinc and mercury were carried out. 2. The GF-AAS method and DPC method for the determination of total chromium in seawater are compared. The purpose of this paper is to investigate the practical application of the two methods in laboratory. The detection limits of total chromium in seawater by GF-AAS method and DPC method are 0.17 渭 g / L ~ (-1) ~ 0.11 渭 ig/L, respectively. The relative standard deviation in the laboratory was 4.52-5.42 and 4.90-5.31, respectively. The recoveries were 102.3and 103.5and 98.2and 101.6.The relative standard deviations in the laboratory were 4.52-5.42 and 4.90-5.31, respectively. 3. The GF-AAS method and ASV method for the determination of copper, lead and cadmium in seawater were compared. The detection limits of GF-AAS and ASV methods were 0.10 渭 gL,2.33 渭 g / L and 0.10 渭 gL,2.33 渭 g / L, respectively. The recoveries were 101.5 and 107.7, respectively, and the relative standard deviations in the laboratory were 4.56- 6.59, respectively. The detection limits of lead in seawater by 11.60%~19.41%.GF-AAS and ASV were 0.38 渭 g / L and 0.38 渭 g / L, respectively. The recoveries of standard addition were 100.7- 101.0 and 97.8- 143.2, respectively. The relative standard deviations in the laboratory were 3.71 and 8.56 and 16.699.The detection limits of cadmium in seawater by GF-AAS and ASV were 0.15 渭 g / L and 0.02 渭 g / L, respectively. The recoveries were 98.0-98.8 and 99.8- 107.1, and the relative standard deviations in the laboratory were 4.11-5.02 and 8.22-8.71, respectively. 4. The FAAS method and ASV method for the determination of zinc in seawater were compared in order to investigate the laboratory application of the two methods. The detection limits of FAAS method and ASV method for the determination of zinc in seawater were 1.73 渭 g / L ~ (-1) 渭 g / L ~ (-1) ~ (-1) 渭 g 路L ~ (-1), respectively. The recoveries were 101.1% -103.7% and 138.7% -145.9%, respectively. The relative standard deviations in the laboratory were 2.93-3.12 and 16.767.11, respectively. 5. The CAAS method and AFS method for the determination of mercury in seawater were compared to investigate the laboratory application of the two methods. The detection limits of CAAS method and AFS method for the determination of mercury in seawater were 0.010 渭 g / L ~ 0.008 渭 g 路L ~ (-1) 路L ~ (-1), respectively. The relative standard deviation in the laboratory was 0.670.990.86 and 1.92, respectively. 6. According to the experimental data, considering the detection limit, accuracy and precision of the method, the pretreatment process and the complexity of the method, the GF-AAS method is recommended for the determination of total chromium, copper, lead and cadmium in seawater, and the FAAS method for the determination of zinc in seawater is recommended. AFS method was used to determine mercury in seawater.
【学位授予单位】：大连理工大学
【学位级别】：硕士
【学位授予年份】：2015
【分类号】：X834

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