Improved method for Hf separation from silicate rocks for isotopic analysis using Ln-spec resin column
Improved method for Hf separation from silicate rocks for isotopic analysis using Ln-spec resin column
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DOI：
10.2465/jmps.091011
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发表时间：
2010-12
影响因子：
0.7
通讯作者：
R. Shinjo;Yuko Ginoza;Daniel Meshesha
中科院分区：
文献类型：
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作者：
R. Shinjo;Yuko Ginoza;Daniel Meshesha
本文提出了一种改进的热电离质谱（TIMS）和多接收电感耦合等离子体质谱（MC-ICP-MS）化学分离法测量铪同位素比值的方法。在第一个柱（2.5-ml Eichrom Ln-spec树脂）中，在洗涤主要元素HREE、Ti、Nb和Zr之后，用2 M HCl-0.2M HF收集Hf馏分。对于进一步的Hf纯化，以与第一柱类似的方式进行第二柱（1-ml Ln-spec树脂）化学。第一个色谱柱设计用于处理0.5克硅酸盐岩石样品进行TIMS分析。因此，由于MC-ICP-MS分析所需的Hf量远小于TIMS分析所需的Hf量，因此MC-ICP-MS分析的柱化学可以根据消化样品的量按比例缩小。尽管需要改进TIMS技术，但是在应用所提出的分离方法之后，获得的地质参考岩石和埃塞俄比亚溢流玄武岩的TIMS Hf数据在分析误差内与先前报道的使用MC-ICP-MS获得的数据一致。所提出的方法的优点包括减少所使用的试剂的量（因此，相应地减少了空白贡献），减少了所需的时间，并且简化了需要较少数量的酸的制备。
An improved chemical separation method for Hf isotope ratio measurement using both the thermal ionization mass spectrometer (TIMS) and the multiple collector-inductively coupled plasma-mass spectrometer (MC-ICP-MS) is presented in this paper. In the first column (2.5-ml Eichrom Ln-spec resin), Hf cut was collected with 2M HCl-0.2M HF after washing the major elements, HREE, Ti, Nb, and Zr. For further Hf purification, the second column (1-ml Ln-spec resin) chemistry was conducted in a manner similar to that of the first column. The first column is designed for treatment with a 0.5-g silicate rock sample for TIMS analysis. Thus, because the Hf amount required for MC-ICP-MS analysis is much lesser than that required for TIMS analysis, the column chemistry for MC-ICP-MS analysis can be scaled down, depending on the amount of digested sample. Although there is a need to improve the TIMS technique, the TIMS Hf data obtained for geological reference rocks and Ethiopian flood basalts after the application of the proposed separation methods are consistent, within analytical error, with the previously reported data obtained using the MC-ICP-MS. The advantages of the proposed method include a reduction in the amount of reagents used (hence, a consequent reduction in the blank contribution), reduction in the time required, and a simplified preparation requiring a fewer number of acids.