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1.
废线路板粉末中二噁英含量的测定   总被引:1,自引:1,他引:0  
采用加速溶剂萃取-柱层析-高分辨质谱法检测废线路板粉末样品中17种2,3,7,8-PCDD/Fs的含量。采用TRDIOXIN-5MS毛细管色谱柱(60 m×0.25 mm×0.25μm)进行分离和多离子检测(MID)模式进行检测,以保留时间和同位素特征离子丰度比进行定性,用13C标记同位素稀释内标法进行定量。结果表明,17种2,3,7,8-PCDD/Fs化合物的标准曲线的线性相关性良好,线性相关系数均大于0.999 9,该方法分析的提取内标的平均回收率范围为37.25%~82.75%,RSD8%,样品中各异构体的加标回收率为112.66%~124.26%,RSD7%。应用该方法检测废线路板粉末样品,回收率在58.67%~123.00%范围内,1,2,3,4,6,7,8-Hp CDF、1,2,3,4,6,7,8-Hp CDD、OCDF、OCDD的质量比分别为2.74、2.50、5.57、16.37 pg/g,TEQ分别为0.027 4、0.025 0、0.005 6、0.016 4 ng/kg。  相似文献   

2.
文章采用电感耦合等离子体光谱法测定土壤中As、Cd、Cu、Cr、Hg、Ni、Pb、Zn共8种重金属元素,与传统标准方法原子吸收光谱法进行了结果比对、并且通过加标回收率以及标准物质的测试进行验证,得出:电感耦合等离子体光谱法满足HJ/T166-2004《土壤环境监测技术规范》以及GB15618-2018《土壤环境质量农用地土壤污染风险管控标准》中对重金属检测的要求,并且该方法的检出限较低,满足土壤中重金属污染风险筛选值的要求;标准曲线测量范围宽,达到两个数量级,可满足各种含量土壤中重金属的测试;精密度均小于1%,重复性好,结果稳定可靠;线性拟合系数R=0.999~0.99999;与原子吸收法检测结果比对良好,加标回收率以及标准物质测试准确度高。该方法一次进样同时得到所需元素的结果,极大地提高检测工作效率,降低检测工作成本,适用于大批量检测土壤中重金属的含量。  相似文献   

3.
建立了针对地表水和地下水中11种三嗪类农药的超高效液相色谱三重四极杆质谱分析方法,并对前处理、仪器分析、方法特性指标等因素进行优化探讨。使用SB-C18色谱柱、乙腈水二元混合液流动相进行化合物分离,设置柱温为40℃、进样量为10μL,质谱采用正离子模式检测,内标法定量,采用平均相对响应因子法拟合标准曲线。结果表明,11种三嗪类农药的方法检出限为0.003~0.01μg/L,对3种质量浓度的基体加标样品分别进行6次平行分析,测定结果的相对标准偏差为2.1%~19%,平均加标回收率为80.0%~108%。采集地表水和地下水样品,经尼龙或聚四氟乙烯滤膜过滤后上机测定,在1种地表水样品中检出了阿特拉津和扑灭津,平均质量浓度分别为0.032和0.009μg/L。该方法具有准确度高、重复性好、检出限低等优点,能够满足现阶段地表水和地下水的环境管理监测要求。  相似文献   

4.
为了探究土壤中苯胺回收率测定偏低的难点,笔者针对《土壤和沉积物 苯胺类和联苯胺类的测定 液相色谱-三重四极杆质谱法(征求意见稿)》中前处理阶段的问题,在优化部分前处理条件的基础上,研究土壤吸附、内标加入的时机以及还原剂(五水合硫代硫酸钠)和氨水对苯胺回收率的影响。结果表明:土壤吸附是导致苯胺加标回收率偏低的重要因素,与空白加标相比,含有一定量有机质的砂质壤土基体加标回收率减少了42.05%~60.89%。内标在不同阶段加入会对苯胺回收率产生显著影响,主要是由前处理过程中的基体吸附和挥发损失导致。加入还原剂和氨水对空白加标的苯胺回收率无显著影响,但对于含有一定量有机质的砂质壤土,加入氨水后苯胺加标回收率增加了59.57%,具有显著影响。  相似文献   

5.
探讨了利用液相色谱分离,荧光检测器测定地表水中联苯胺的可行性。前处理方法对比验证了液液萃取法和固相萃取法。水样在碱性条件下(pH=11~12)进行提取,当提取体积为1.0 L时,液液萃取液相色谱荧光法检测,方法检出限为1.4 ng/L,定量下限为5.5 ng/L;固相萃取液相色谱荧光法检测,方法检出限为0.9 ng/L,定量下限为3.6 ng/L。分别对地表水、生活废水、工业废水3种不同水体进行基体加标试验,加标浓度为10.0、40.0、80.0 ng/L。结果显示,对于3种不同基体和不同加标浓度的水样,两种方法均有较好的准确性和重现性,方法回收率为80%~120%,相对标准偏差均小于20%,满足《地表水环境质量标准》(GB 3838—2002)中对联苯胺的监测需求。  相似文献   

6.
报道了用ICP-MS法直接测定水稻田表层土壤中的重金属元素Zn、Cd、Pb、Cu、Cr、Mn含量的方法.土壤样品经HNO3-HF-HClO4彻底消化后,加入内标元素45Sc、115In、204Tl,采用内标法进行测定,有效地克服了基体效应、接口效应及仪器波动所产生的影响;通过优化仪器的工作参数,选择待测元素适当地测定同位素,有效克服了因质谱干扰所带来的影响.对污染土壤标准物质(编号GBW08305)进行测定,测定结果与标准值相吻合.该方法的加标回收率是98.0%~102.0%,相对标准偏差是2.2%~3.5%,具有线性范围宽、简单、快速、准确等特点.  相似文献   

7.
介绍了原子吸收光度法中的光谱干扰和非光谱干扰,指出标准加入法和分析校准曲线法是消除和减少某些干扰最简单、快速的校准方法。在标准加入法中,当分析曲线呈线性时,表明分析结果可信,当分析曲线不呈线性,表明方法灵敏度随质量浓度变化而变化,分析结果的准确性有问题。以改变基体的质量浓度和在同一质量浓度的基体溶液中加入不同量的标准两个实验可以验证标准加入法在原子吸收光度法中的适用性。  相似文献   

8.
采用4种微波消解体系对聚四氟乙烯(PTFE)材质滤膜采集的PM2.5样品进行消解,利用电感耦合等离子体质谱(ICP-MS)测定样品中Cr、Mn、Cu、As、Cd 5种重金属元素含量,并计算其空白加标和样品加标回收率,建立了测定PTFE材质滤膜采集的PM2.5样品中重金属元素的最优微波消解体系。结果表明,4种消解体系下,空白加标回收率和样品加标回收率均处于合理范围,分别为95.3%~116.3%和93.3%~118.5%。其中,HNO3放置过夜+H2O2消解体系具有空白值低、测定稳定性强、操作简便、绿色环保、对人体健康危害小等优点,能够满足大批量PM2.5样品中重金属总量的快速、高效、准确分析的要求。  相似文献   

9.
采用改良后的沉淀集卵法对低(10个/100 g)、中(20个/100 g)、高(40个/100 g)3种不同浓度的加标样品进行蛔虫卵检测,比较其回收率。结果表明:不同浓度加标样品的回收率为高浓度中浓度低浓度。与相关文献实验结果比较表明,该方法不仅回收率较高、稳定性较好,且在检测低浓度样品时较漂浮集卵法具有一定优势。  相似文献   

10.
用二氯甲烷索氏提取法对比多种萃取剂超声波提取法测定标准土壤样品回收率的结果,以实验得出二氯甲烷超声波提取法的样品加标回收率及相对标准偏差。结果表明,二氯甲烷超声萃取法提取土壤中的半挥发性有机物的时效性,准确性能够满足监测分析的要求。  相似文献   

11.
For highly urbanized cities where there is a scarcity of land available for landfilling, incineration of refuse is a feasible solution for solid waste disposal. After incineration, about 20% by weight of fly ash and other residues are produced and disposed of by landfill. Leachate tests carried out on samples of fly ash show that the heavy metal concentrations of the leachate are in excess of the permissible limits set by WHO. Lime and cement are used to stabilize the fly ash. The concentrations of heavy metals in the leachates of lime and cement treated fly ash are non-detectable. In additional to pollution control, the lime and cement treated fly ash significantly improves the properties of soft clay.  相似文献   

12.
以广东某铅锌冶炼厂的废旧除尘布袋及其布袋上的飞灰为实验材料,以HNO3-H2O2-HF对布袋及飞灰进行微波全量消解,采用BCR三步浸提法提取飞灰中Cu、Zn、Pb、Cr、Ni、Cd 6种重金属,并利用火焰原子吸收仪器检测布袋及飞灰中6种重金属的含量及飞灰中各形态含量。结果表明,铅锌冶炼厂废旧布袋和飞灰中重金属含量较高,远大于《国家土壤环境质量标准》(GB 15168—1995)三级标准值。不同重金属在飞灰中的形态分布差异较大,Ni主要以残渣态和酸可交换态为主,Cu和Pb以残渣态为主,Zn的4种形态分布都较均匀,Cd、Zn潜在的迁移性最强。  相似文献   

13.
Although many leaching methods have been used for various purposes by research groups, industries, and regulators, there is still a need for a simple but comprehensive approach to leaching coal utilization by-products and other granular materials in order to estimate potential release of heavy metals when these materials are exposed to natural fluids. A serial batch characterization method has been developed at the National Energy Technology Laboratory that can be completed in 2–3 days to serve as a screening tool. The procedure provides an estimate of cumulative metals release under varying pH conditions, and leaching the sample at increasing liquid/solid ratios can indicate the rate at which this process will occur. This method was applied to eight fly ashes, adapted to the acidic or alkaline nature of the ash. The leachates were analyzed for 30 elements. The test was run in quadruplicate, and the relative standard deviation (RSD) was used as a measure of method reproducibility. RSD values are between 0.02 and 0.70, with the majority of the RSD values less than 0.3. The serial batch leaching procedure was developed as a simple, relatively quick, yet comprehensive method of estimating the risk of heavy metal release from fly ash when it is exposed to natural fluids, such as acid rain or groundwater. Tests on a random selection of coal fly ashes have shown it to be a reasonably precise method for estimating the availability and long-term release of cations from fly ash.  相似文献   

14.
A European standard for the determination of Cr(vi) in solid material has been elaborated in the framework of an international co-operation and finally validated in the course of an interlaboratory comparison. The procedure is based on the alkaline digestion prescribed by EPA method 3060A followed by ion chromatography and determines an operationally defined content of Cr(vi), including water-soluble and insoluble chromates. A preliminary robustness study was carried out in order to compare different extraction methodologies and to study the equivalency of different analytical methods for the determination of Cr(vi) in alkaline extracts of soil and waste materials. During an interlaboratory validation trial with 19 European laboratories a set of 4 samples (2 soil and 2 waste samples) was analysed to determine performance characteristics for different combinations of digestion and detection methods. With the procedures prescribed by the new European standard (EN 15192) acceptable results were obtained for both soil samples and one of the waste samples (sludge). However, for the second waste sample (fly ash) a large deviation in analytical results was observed. This indicates that particularly for waste materials a possible occurrence of strong matrix effects has to be considered and supplementary quality control data are needed in order to assess the validity of analytical results. The accuracy of the determination of Cr(vi) in solid matrices remains a challenging field in terms of maximum extraction efficiency and minimum species interconversion.  相似文献   

15.
This paper provides a comprehensive characterization of mineral waste such as fly ash, bottom ash, slag and construction demolition (C&D) collected from four different thermal power plants, three steel plants and three C&D waste generation sites in India. To determine utilisation potential and environmental concerns, as received fly ash, bottom ash, slag and C&D waste were analysed for physico-chemical, mineralogical and morphological properties. The physico-chemical properties analysed include pH, moisture content, acid insoluble residue, loss on ignition(LOI), carbon content, fineness, chloride content, sulphate content, reactive silica content, XRF and heavy metal analysis. Morphological and mineralogical characteristics were investigated using scanning electron microscopy–energy dispersive X-ray. Particle size distribution was obtained using particle size analyser. The material analysed has different compositions and were selected with a view to determine their suitability for different applications in cement and concrete industry and for further research studies.  相似文献   

16.
中国现行的固体废物氰化物总量和氰化物浸出毒性的分析方法存在缺陷,不便于广泛指导监测工作,笔者优化了固体废物氰化物测定的前处理方法,明确了固体废物氰化物总量、氰化物浸出毒性测定时的样品粒径、浸提方法和消解方法,建立了容量法、分光光度法、流动注射法测定固体废物氰化物总量和浸出毒性的方法,并与标准方法(离子色谱法)进行比较。实验结果表明:容量法、分光光度法、流动注射法测定结果与离子色谱法无显著差异,3种方法测定固体废物氰化物总量加标回收率为80.5%~102%,平行样测定相对标准偏差为3.0%~6.9%,3种方法测定固体废物氰化物浸出毒性加标回收率为80.1%~107%,平行样测定相对标准偏差为7.8%~9.5%,3种方法测定结果精密度和准确度良好,均能够满足固体废物氰化物总量和氰化物浸出毒性的测定要求。其中容量法、分光光度法由于其仪器设备简单、操作简便,可用于突发环境事件应急监测等情况下固体废物氰化物的测定。但容量法检出限较高,不能满足评价标准较低的分析测试工作要求,离子色谱法、分光光度法和流动注射法检出限均能满足一般分析测试要求。  相似文献   

17.
Municipal solid waste incineration (MSWI) is a straightforward way to manage waste, however the disposal of process byproducts, mainly bottom and fly ash, is still a problem, because of their hazardous contents. Fly ash is a byproduct of many other processes that involve combustion to produce energy. In this paper we present and discuss a new method for MSWI fly ash inertization, mainly based on the use of colloidal silica as a stabilization agent for metals. In the patented procedure, fly ash of different provenance can be used to produce an inert and non-hazardous material, that can be reused. In fact to make the recovery process more efficient, landfilling should be totally avoided. For this reason, to enhance the possibility of reuse, a washing process, for salts recovery, is proposed as a final step of the inertization procedure. The obtained inert material is called COSMOS (COlloidal Silica Medium to Obtain Safe inert), and it is composed of calcium carbonate, calcium sulfate, silicon oxide and a wide quantity of non-soluble amorphous compounds. COSMOS does not contain any corrosive salts. This makes it extremely interesting for cement industry applications with several other advantages, and environmental benefits. The new proposed inertization procedure appears very promising, because it allows MSWI fly ash to be considered a valuable resource. Thanks to the obtained results, a demonstration project, in the frame of LIFE+, has been funded by the European Commission (LIFE+ 2008 project ENV/IT/000434, ).  相似文献   

18.
石河子燃煤电厂重金属排放研究   总被引:3,自引:2,他引:1  
万勤  孟优  陈平  李杰 《中国环境监测》2015,31(6):129-133
选取石河子市典型燃煤电厂,对其燃煤烟气重金属排放浓度及飞灰、底渣、脱硫石膏重金属的富集进行定量分析。结果表明,烟气中各重金属排放浓度从高到低依次为Zn、Ni、Cr、Pb、Cu、Hg、Co、Cd、As。各重金属元素在飞灰中的富集程度较高,除Hg、Cd、Ni外,其他重金属元素在飞灰的富集因均值均大于5。其中,As在飞灰的富集因子均值为5.76。研究结果可为石河子重金属污染控制提供基础数据。  相似文献   

19.
Fly ash samples were taken from solid waste incinerators with different feeding waste, furnace type, and air pollution control device in six cities of Zhejiang province. The solid waste incinerators there constitute one fifth of incinerators in China. Heavy metals and polychlorinated dibenzo-p-dioxins and dibenzofurans (PCDD/Fs) were analyzed in the fly ash. Moreover, the fly ash samples were extracted by toxicity characteristic leaching procedure (TCLP). The biotoxicity of the leachate was evaluated by Chlorella pyrenoidosa. High variation and contents were found for both the heavy metals and PCDD/Fs. The contents of Zn, Cu, As, Pb, Cd, Cr, Ni, and Hg in the fly ash samples varied from 300 to 32,100, 62.1–1175, 1.1–57, 61.6–620, 0.4–223, 16.6–4380, 1.2–94.7, and 0.03–1.4 μg g−1 dw, respectively. The total contents of 17 PCDD/Fs varied from 0.1128 to 127.7939 μg g−1 dw, and the 2,3,7,8-TeCDD toxic equivalents (TEQ) of PCDD/Fs ranged from 0.009 to 6.177 μg g−1 dw. PCDF congeners were the main contributor to the TEQ. The leachate of the fly ash showed biotoxicity to C. pyrenoidosa. A significant correlation was found between the Cd and EC50 values. Further research is required to investigate the environmental impact of the various pollutants in the fly ash.  相似文献   

20.
The chromium species leaching from a coal combustion fly ash landfill has been characterized as well as a novel approach to treat leachates rich in hexavalent chromium, Cr(VI), by using another natural waste by-product, acid mine drainage (AMD), has been investigated during this study. It is observed that as much as 8% (approximately 10 microg g(-1) in fly ash) of total chromium is converted to the Cr(VI) species during oxidative combustion of coal and remains in the resulting ash as a stable species, however, it is significantly mobile in water based leaching. Approximately 1.23 +/- 0.01 microg g(-1) of Cr(VI) was found in the landfill leachate from permanent deposits of aged fly ash. This study also confirmed the use of AMD, which often is in close proximity to coal combustion by-product landfills, is an extremely effective and economical remediation option for the elimination of hexavalent chromium in fly ash generated leachate. Speciated isotope dilution mass spectrometry (SIDMS), as described in EPA Method 6800, was used to analytically evaluate and validate the field application of the ferrous iron and chromate chemistry in the remediation of Cr(VI) runoff.  相似文献   

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