火试金富集-自动电位滴定法测定粗碲中的银含量

Determination of Silver Content in Crude Tellurium by Automatic Potentiometric Titration

粗碲是由铜、铅、锌冶炼带来的副产品,其中含有大量的金、银等贵金属。快速准确检测粗碲中银含量,具有十分重要的意义。样品预先采用硫酸溶解,还原沉淀金、银,过滤分离大部分的铋、硒、碲等元素,经配料、高温熔融,熔融态的金属铅捕集试料中的贵金属形成铅扣,试料的其他物质与熔剂生成易熔性熔渣。将铅扣灰吹,得金银合粒,清除合粒表面粘附的杂质,经硝酸分金,用硫氰酸钾滴定法测定银量。银的加标回收率在99.5%~101%,相对标准偏差(RSD)小于5%。方法速度快,稳定性好,适用于粗碲中银含量的测定。

Crude tellurium is a by-product in the smelting process of copper,plumbum and zinc,which contains a lot of precious metal such as gold and silver.Determining of crude tellurium in the precious metal rapidly and accurately has important practical significance.In this method,sulfuric acid is dissolved in advance,and gold and silver were reduced and precipitated.Most elements such as bismuth,selenium and tellurium were separated by filtration.By batching and melting,molten plumbum chelate precious metal to form lead buckle,and others form molten slag.Determining of silver content by rhodanometry method after cupellation process and removing impurity of gold-silver complex particle.The spiked recovery rate of silver was 99.5%—101%,and the relative standard deviation was less than 5%.This method has fast analysis speed and good stability,which is suitable for the determination of silver content in crude tellurium.