Selective extractions to assess the biogeochemically relevant fractionation of inorganic mercury in sediments and soils
Selective extractions to assess the biogeochemically relevant fractionation of inorganic mercury in sediments and soils
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DOI：
10.1016/s0003-2670(02)01550-7
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发表时间：
2003-03-10
影响因子：
6.2
通讯作者：
Hiltner, M
中科院分区：
文献类型：
--
作者：
Bloom, NS;Preus, E;Hiltner, M
在这里，我们提出了一种新的方法，顺序选择性提取（SSE）的地质固体中的汞，验证了广泛的质量保证程序。汞被分离成在地球化学上“有意义”的部分，而不是通过特定的化合物来识别。实验阐明了提取时间、固液比和替代溶剂对天然样品、参比物质和纯化合物的影响。测试的化合物包括HgS（红色和黑色）、HgCl 2、Hg-0、（HgCl 2）-Cl-2、HgSe、HgO、吸附在针铁矿上的Hg（II）、Hg-Humate和金汞齐化Hg。基于这些发现，建立了一个五步提取序列，将化合物分离成地球化学上不同的类别。级分和浸提介质如下：F1（去离子水）、F2（0.01 M HCl + 0.1 M CH 3COOH）、F3（1 M KOH）、F4（12 M HNO 3）和F5（王水）。方法空白和方法检测限（MDLs）为0.1-5纳克/克的各种分析馏分，这取决于所使用的试剂浓度。对于样品中的主要级分，精密度范围为2 - 8%，但对于组成样品的级分，精密度增加至2-40%。
Here we present a new method for sequential selective extractions (SSEs) for Hg in geological solids, validated with extensive quality assurance procedures. Mercury was separated into fractions which "make sense" biogeochemically, rather than being identified by specific compounds. Experiments elucidated the effects of extraction time, solids-to-liquid ratio, and alternate solvents in natural samples, reference materials, and pure compounds. Compounds tested included HgS (red and black), HgCl2, Hg-0, (HgCl2)-Cl-2, HgSe, HgO, Hg(II) adsorbed on goethite, Hg-humate, and gold amalgamated Hg. Based on these findings, a five-step sequence of extractions was established to separate the compounds into biogeochemically distinct categories. The fractions and leaching media were as follows: F1 (deionized water), F2 (0.01 M HCl + 0.1 M CH3COOH), F3 (1 M KOH), F4 (12 M HNO3) and F5 (aqua regia). Method blanks and method detection limits (MDLs) of 0.1-5 ng/g were obtained for the various analytical fractions, depending on the reagent concentrations used. Precision ranged from 2 to 8% for the major fractions in a sample, but increased to 2-40% for fractions making up