Zawisza Beata
Institute of Chemistry, Silesian University, ul. Szkolna 9, 40-006 Katowice, Poland.
Anal Chem. 2008 Mar 1;80(5):1696-701. doi: 10.1021/ac702015a. Epub 2008 Feb 2.
X-ray fluorescence spectrometry method is subject to certain difficulties and inconveniences for the elements having the atomic number 9 or less. These difficulties become progressively more severe as the atomic number decreases, and are quite serious for beryllium, which is practically indeterminable directly by XRF. Therefore, an indirect determination of beryllium that is based on the evaluation of cobalt in the precipitate is taken into consideration. In the thesis below, there is a description of a new, simple, and precise method by selective precipitation using hexamminecobalt(III) chloride and ammonium carbonate-EDTA solution as a complexing agent for the determining of a trace amount of beryllium using X-ray fluorescence spectrometry. The optimum conditions for [Co(NH(3))(6)][Be(2)(OH)(3)(CO(3))(2)(H(2)O)(2)].(3)H(2)O complex formation were studied. The complex was collected on the membrane filter, and the Co Kalpha line was measured by XRF. The method presents the advantages of the sample preparation and the elimination of the matrix effects due to the thin film obtained. The detection limit of the proposed method is 0.2 mg of beryllium. The method was successfully applied to beryllium determination in copper/ beryllium/cobalt alloys.
对于原子序数为9及以下的元素,X射线荧光光谱法存在一定困难和不便。随着原子序数降低,这些困难愈发严重,对于铍而言尤为严重,实际上无法直接用X射线荧光光谱法测定铍。因此,考虑采用基于沉淀物中钴含量评估的铍间接测定法。在下文的论文中,描述了一种新的、简单且精确的方法,即使用六氨合钴(III)氯化物和碳酸铵 - 乙二胺四乙酸(EDTA)溶液作为络合剂,通过选择性沉淀,利用X射线荧光光谱法测定痕量铍。研究了[Co(NH(3))(6)][Be(2)(OH)(3)(CO(3))(2)(H(2)O)(2)].(3)H(2)O络合物形成的最佳条件。该络合物收集在膜滤器上,通过X射线荧光光谱法测量钴的Kα线。该方法具有样品制备的优势,并且由于获得的薄膜消除了基体效应。所提出方法的检测限为0.2毫克铍。该方法已成功应用于铜/铍/钴合金中铍的测定。