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改进BCR法-电感耦合等离子体发射光谱法测定矿产品堆场土壤中镉砷铅的化学形态 总被引：5，自引：2，他引：3
矿产品堆场土壤中重金属在环境中富集,随着元素的迁移、转化及地下水的循环,成为环境污染问题。本文将改进的顺序提取法(BCR)应用于矿产品堆场土壤中Cd、As、Pb的化学形态分析,结合这三种元素的性质,将堆场土壤中Cd、As、Pb分为可交换态、可还原态、可氧化态和残渣态,并利用电感耦合等离子体发射光谱法测定其含量。采用形态分析标准参考物质GBW 07436验证了三步提取态的准确性,并对6个矿产品堆场土壤中Cd、As、Pb形态含量进行分析,三步提取态加上残渣态质量分数之和与重金属总量进行了比较,回收率为85.54%~102.88%。通过对矿产品堆场土壤实际样品分析,Cd、As、Pb三种元素非残渣态含量顺序为Cd(79.40%~94.94%)Pb(24.27%~37.73%)As(22.89%~31.51%),表明Cd元素较为容易进入生物圈。该方法解决了港口堆场土壤中重金属化学形态提取问题,对污染土壤的治理具有指导意义。 相似文献
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以三门湾表层沉积物为研究对象,对5种重金属(Zn、Cr、Cd、Cu、Pb)的含量分布、赋存形态进行分析,并运用潜在生态危害指数法、Risk Assessment Code(RAC)法、次生相与原生相比值法对重金属生态风险进行了评价。结果表明:三门湾表层沉积物重金属的含量分布整体表现为湾内高于湾外海域,人类活动是主要影响因素。运用BCR法对沉积物中重金属进行分级提取,结果显示 Zn、Cd、Cr、Cu均以残渣态为主要赋存形态(Zn:79.20%~84.25%、Cr:93.24%~96.16%、Cd:34.71%~57.58%、Cu:66.06%~79.51%),而Pb以可还原态为主(56.58%~76.44%)。评价结果中,潜在生态危害指数法和次生相与原生相比值法均显示湾内的重金属污染比湾外严重,而RAC法指出Pb污染为湾外高于湾内海域;潜在生态危害指数法和RAC均指出Cd是主要污染元素;在次生相与原生相比值法中Pb则是主要危害元素,Cd次之。 相似文献
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A Rapid Method for Determining Boron Concentration (ID‐ICP‐MS) and δ11B (MC‐ICP‐MS) in Vegetation Samples after Microwave Digestion and Cation Exchange Chemical Purification 
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下载免费PDF全文 Philippe Roux Damien Lemarchand Harold J. Hughes Marie‐Pierre Turpault 《Geostandards and Geoanalytical Research》2015,39(4):453-466
We present in this article a rapid method for B extraction, purification and accurate B concentration and δ11B measurements by ID‐ICP‐MS and MC‐ICP‐MS, respectively, in different vegetation samples (bark, wood and tree leaves). We developed a rapid three‐step procedure including (1) microwave digestion, (2) cation exchange chromatography and (3) microsublimation. The entire procedure can be performed in a single working day and has shown to allow full B recovery yield and a measurement repeatability as low as 0.36‰ (± 2s) for isotope ratios. Uncertainties mostly originate from the cation exchange step but are independent of the nature of the vegetation sample. For δ11B determination by MC‐ICP‐MS, the effect of chemical impurities in the loading sample solution has shown to be critical if the dissolved load exceeds 5 μg g?1 of total salts or 25 μg g?1 of DOC. Our results also demonstrate that the acid concentration in the sample loading solution can also induce critical isotopic bias by MC‐ICP‐MS if chemistry of the rinsing‐, bracketing calibrator‐ and sample solutions is not thoroughly adjusted. We applied this method to provide a series of δ11B values of vegetal reference materials (NIST SRM 1570a = 25.74 ± 0.21‰; NIST 1547 = 40.12 ± 0.21‰; B2273 = 4.56 ± 0.15‰; BCR 060 = ?8.72 ± 0.16‰; NCS DC73349 = 16.43 ± 0.12‰). 相似文献
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The concentrations of Cr, Mn, Fe, Ni, Cu, Zn, and Pb metals in soil samples (N = 21) were determined by flame atomic absorption spectrometry. The modified Community Bureau of Reference (BCR) sequential extraction procedure (three‐step) was used in order to evaluate mobility, availability, and persistence of heavy metals in soil samples taken from an agricultural area in Erciyes University Campus. The operationally defined fractions isolated using the BCR procedure were: acid extractable, reducible, and oxidizable. The mobility sequence based on the sum of the BCR sequential extraction stages was: Mn (70.2%) > Pb (62.9%) > Ni (26.7%) > Cr (15.4%) > Zn (14.4%) > Cu (12.9%) > Fe (1.24%). Multivariate statistical analysis was used to define the possible origin of heavy metals in soils. Correlation analysis, principal component analysis (PCA), and cluster analysis (CA) were applied to the data matrix to evaluate the analytical results and to identify the possible pollution sources of heavy metals. PCA results revealed that the sampling area was mainly influenced from three sources, namely natural, airborne emissions from domestic heating and traffic. 相似文献
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钙、铁、铝形态对岩溶石灰土磷有效性的影响 总被引：2，自引：1，他引：1
为揭示钙、铁、铝形态与岩溶地区土壤磷有效性关系,通过改进的BCR元素形态连续提取法获取石灰土不同发育阶段土壤矿质元素赋存形态,并分析与总磷及速效磷含量之间的相关关系。初步研究表明:石灰土壤中全磷和速效磷在石灰土发育过程呈降低趋势,从黑色石灰土到黄色石灰土,总磷降低了76.7%,速效磷减少了84.7%。石灰土总磷与速效磷同酸溶态、可还原态及残渣态钙,可氧化态铁、铝和可还原态铝显著正相关,而同总铁、总铝以及残渣态铝显著负相关,相关系数绝对值均达到0.9以上。随着石灰土发育进行,钙总量及其形态均降低,而铝、铁总量和形态呈增加趋势,可能导致岩溶地区石灰土磷及其有效性缺乏越发突出。 相似文献
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Yonghua LI Linsheng YANG Wuyi WANG 《中国地球化学学报》2006,25(B08):244-244
Western Hunan Province is one of the most typical assembling areas of cryogenic metallic deposit in China, as well as a main ore-forming zone for some heavy metals. In the region, Hg and Pb pollution was caused by abnormally high concentrations of Hg, Pb in the natural environment and Hg, Pb exploiting/smelting and other human activities, which make the damage to human health more complicated. Generally, heavy metal pollutants in soil are often long-lasting and consequent, with their emission and/or transport into the environment, resulting in growing hazards to human health posed by elevated heavy metal concentrations in air, water, and food. Therefore, monitoring and understanding their behaviors in soil environment is the most important and urgent task. In this paper, the environmental behaviors and pollution characteristics of soil polluted by Hg and Pb in typical Hg and Pb mining areas in western Hunan were studied. Main results are presented as follows： （1） Western Hunan Province is a high regional geochemical abnormal region on Hg and Pb. The concentrations of Hg and Pb in soils in mercury mining areas were 1 315 and 3. l times higher than the average background of soils in China, respectively. While those in soils in lead mining areas are 14.1 and 6.1 times higher. By using the index of geoaccumulation （Igeo）, it was found that either mercury mining area or lead mining area in western Hunan Province has been polluted by the two elements, the majority of soils in mercury mining areas are seriously polluted by Hg, moderately or light polluted by Pb, while the majority of soils in lead mining areas are moderately or moderately-highly polluted by Pb and moderately-highly polluted by Hg. （2） By the BCR extraction procedures, both Hg and Pb in soils are dominated by residual form, followed by organic-sulfide form. Fe-Mn oxides and acid-exchangeable form are rather low. The total concentrations and each species of Hg and Pb in soils show positive correlations with the concentrations of sands, and negative ones with the concentrations of clays in soils. 相似文献
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土壤中铜的地球化学形态决定了其在环境中的释放、变化形式、迁移规律及生物效应。通过对德兴铜矿及周边地区82件表层土壤样品,采用改进的BCR提取方法测定铜的地球化学形态,了解其区域分布特征,结果表明:(1)德兴地区土壤中酸可溶态的铜≈可还原态铜<可氧化态铜≈残渣态铜,酸可溶态 可氧化态 可还原态的铜平均质量分数为45.07×10-6,较中国土壤背景值全铜的质量分数(22.6×10-6)高,这些活动态的铜易于进入食物链,对人体健康和生态安全构成潜在的威胁,不同形态铜的区域分布特征相似,主要位于采矿和选矿活动区附近;(2)采用改进的BCR方法提取的土壤中铜的酸可溶态和可氧化态和采用EDTA提取的可交换态具有明显的正相关关系,土壤pH值增大时酸可溶态铜的比例降低,土壤TOC含量增加时可氧化态铜的比例增大,而土壤CEC对BCR方法提取铜的形态影响不大。 相似文献