The micro-determination of ferrous iron in silicate minerals by a volumetric and a colorimetric method
The micro-determination of ferrous iron in silicate minerals by a volumetric and a colorimetric method
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DOI：
10.1039/an9608500823
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发表时间：
1960
期刊：
影响因子：
4.2
通讯作者：
A. D. Wilson
中科院分区：
文献类型：
--
作者：
A. D. Wilson
本文介绍了以毫克为单位测定样品中二价铁的方法。在室温下，用含有五价钒的氢氟酸分解，使亚铁进入溶液时氧化。在容量法中，亚铁是通过滴定过量的钒来测定的。利用V ~（5+）+Fe ~（2+）+V ~（4+）+Fe ~（3+）反应的可逆性进行比色测定，并用联吡啶测定亚铁的再生成量，在测定硅酸盐岩矿中亚铁含量时，必须采取措施防止分解过程中的大气氧化。例如，密封管用于通过氟硼酸钠熔剂分解耐腐蚀硅酸盐。当样品被热的或沸腾的氢氟酸和硫酸分解时，使用蒸汽或蒸汽加二氧化碳的气氛来防止亚铁的大气氧化，这在氟离子存在下是明显的，可能是由于形成氟化铁络合物。
Methods are described for determining ferrous iron in milligram amounts of sample. Decomposition is effected at room temperature by hydrofluoric acid containing quinquivalent vanadium to oxidise ferrous iron as it passes into solution. In the volumetric method, the ferrous iron is determined by titrating the excess of vanadiumv. The colorimetric determination is carried out by utilising the reversibility of the reaction V5++ Fez++ V4++ Fe3+, and the ferrous iron re-formed is determined by means of dipyridyl.IN the determination of the ferrous iron contents of silicate rocks and minerals, measures have to be taken to prevent atmospheric oxidation during decomposition. For example, a sealed tube is used in the decomposition of resistant silicates by sodium fluoroborate flux, When the sample is decomposed by hot or boiling hydrofluoric and sulphuric acids, l an atmosphere of steam or steam plus carbon dioxide is used to prevent atmospheric oxidation of ferrous iron, which is pronounced in the presence of fluoride ions, presumably owing to the formation of ferric fluoride complexes.