制备高纯度锌所用阳极材料的研究

A Study of the Anode Materials for Producing High-Purity Metallic Zinc

从金属锌制备的源头即在电解过程中关注锌纯度,主要从杂质去除和阳极板合金优化两方面改造锌电解阳极板材料,并对比了新型阳极板和传统铅银阳极板的物理化学性能。通过分析各种元素电化学反应的还原电位,在阳极锌的熔铸过程中加入适量的Al和Cu,使其与Fe、Cd形成稳定的金属间化合物,降低Fe、Cd的还原电位,使它们不在阳极上氧化,进而达到除去目的。通过分析各元素对铅基合金性能的影响,选择添加Ag、Ca、Sr、RE等元素优化阳极板合金。制备的新型阳极板抗拉强度明显提升,硬度有所增强,塑性降低较少,产出的锌产品中Pb、Ni等杂质含量均比传统铅银阳极板低,锌产品纯度有明显提升。

The study aims at better controlling the purity of metallic zinc by improving from its upstream:modificiation of zinc electrolytic anode plate from impurity removal and alloy optimization,and compared the improved anode with the conventional Pb-Ag anode in terms of their physical and chemical performance.During the experiment,after analyzing the reduction potential of various elements in electro-chemical reactions,proper amounts of additives were dosed during the casting process of zinc anode,to form stable intermetallic compounds together with Fe and Cd in order to lower the reduction potential of Fe and Cd,prevent them from oxidation on the anode sheet.After analyzing the effect of various elements on Pb base and metallurgical performance,Ag,Ca,Sr,RE,etc.were chosen as the additives to improve the performance of the anode alloy.The improved anode sheets have shown notable increase in tensile strength,mild increase in hardness,and limited decrease in plasticity.Compared with the product zinc produced with conventional Pb-Ag anodes,the levels of various impurities of product zinc produced with the new node are lower,and the purity of the product zinc has increased markedly.