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高含量钨的测定,长期以来普遍采用重量法,虽然准确度较高,但手续繁杂费时.为了探索简便、快速,准确的测定方法,国内外曾进行了大量研究工作,如氧化还原滴定、络合滴定、沉淀滴定、酸碱滴定等.从氧化还原法来看,过去大多数作者偏重在采用各种还原剂将钨(Ⅵ)还原成三价而滴定;由于钨电子层结构的特点,钨有多种价态(2～6价),并且很难还原到某一恒定的价态上.钨(Ⅴ)硫氰酸盐比色法是一个经典方法,但将其应用于容量法测定钨,则是1976年Yatirajam首次
Determination of high content of tungsten, the weight method has been widely used, although the accuracy is high, but the procedure is complicated and time-consuming.In order to explore the simple, rapid and accurate determination methods, a large number of domestic and foreign studies have been carried out, such as redox titration, network Titration, precipitation titration, acid-base titration, etc. From the point of view of redox method, most authors in the past focused on the reduction of tungsten (VI) to trivalent with various reducing agents and titration. Due to the structure of tungsten electron layer, There are a variety of valence states (2-6 valences), and it is difficult to restore to a constant valence state. Tungsten (Ⅴ) thiocyanate colorimetry is a classic method, but its application to the volumetric method for the determination of tungsten , For the first time in 1976, Yatirajam