Optimizing the Pratt-type titrimetric method to determine FeO in geochemical reference materials
Optimizing the Pratt-type titrimetric method to determine FeO in geochemical reference materials
复制标题
DOI：
10.2343/geochemj.2.0605
复制
发表时间：
2020
影响因子：
0.8
通讯作者：
A. Nakamura;Takashi Okai;Atsuyuki Ohta
中科院分区：
文献类型：
--
作者：
A. Nakamura;Takashi Okai;Atsuyuki Ohta
Copyright © 2020日本地球化学会通过与参考材料的测量值进行比较来验证这些值。在各种类型的湿化学分析中，滴定法是用于测量FeO值的最经典方法之一。虽然滴定法可以得到准确的FeO值，但它很耗时。在使用分析仪器测量FeO方面已经取得了很大进展;这包括新的方法，如离子色谱法（Kanai，1990; le Roex和Watkins，1995），穆斯堡尔光谱法（Lalonde等人，1998）、菲咯啉分光光度法（Husler等人，2011; Tarafder和Thakur，2013）、X射线吸收近边结构（XANES）光谱（Farges，2001; Ohta等人，2006;奥尼尔等人，2006，2018; Berry等人，2010，2018; Cottrell和Kelley，2011; Zhang等人，2018）和电子探针微量分析（EPMA）（Hughes等人，2018年; Li等人，2019年）。在这些发展中，将未知地质样品的结果与地球化学标准物质进行比较至关重要;因此，具有认证值的地球化学标准物质的重要性正在增加。以往地球化学标准物质的定值主要采用滴定法。在该方法中，样品首先在坩埚中用硫酸（H2SO 4）和氢氟酸（HF）分解。然后用重铬酸钾（K2 Cr2 O 7）溶液滴定，以允许FeO量的体积计算。优化Pratt滴定法测定地球化学标准物质中FeO的难度
Copyright © 2020 by The Geochemical Society of Japan. values are validated by comparisons with the measured value of the reference materials. Among various types of wet chemical analyses, titrimetric methods are one of the most classical methods used to measure FeO values. Although titrimetric methods yield accurate FeO values, it is time consuming. Much progress has been made on measuring FeO using analytical instruments; this includes new methods such ion chromatography (Kanai, 1990; le Roex and Watkins, 1995), Mössbauer spectroscopy (Lalonde et al., 1998), phenanthroline spectrophotometry (Husler et al., 2011; Tarafder and Thakur, 2013), X-ray absorption near-edge structure (XANES) spectroscopy (Farges, 2001; Ohta et al., 2006; O’Neill et al., 2006, 2018; Berry et al., 2010, 2018; Cottrell and Kelley, 2011; Zhang et al., 2018), and electron probe microanalysis (EPMA) (Hughes et al., 2018; Li et al., 2019). In each of these developments, it is crucial to compare the results of unknown geological samples with geochemical reference materials; therefore, the importance of geochemical reference materials with certified values is increasing. The certified values of geochemical reference materials have previously been determined mainly by a titrimetric method. During this method, samples are first decomposed by sulphuric acid (H2SO4) and hydrofluoric acid (HF) in crucibles. They are then titrated with a potassium dichromate (K2Cr2O7) solution to allow volumetric calculation of the amounts of FeO. The difficulty arises Optimizing the Pratt-type titrimetric method to determine FeO in geochemical reference materials