(中南工业大学冶金系,长沙410083)
摘 要: 研究了在不同条件(如硫化物试剂、温度、pH值)下生成的镍硫化合物的组成及结构类型。在非氧化还原反应条件下,硫化沉镍产物为NiS。当温度较高(>80℃)、反应速度较快时,产物NiS为属于NiAs结构的α-NiS;当温度较低( < 60℃)、反应较缓慢时,产物为针硫镍型的β-NiS。在有电子得失的硫化沉镍过程中,沉淀产物的组成依沉镍试剂及济液pH值的变化而变化。用硫代硫酸盐沉镍,在任何pH条件下,其产物均为NiS2。在有元素硫存在并参与的沉镍反应中,NiS2总比NiS优先生成。用连二亚硫酸盐(S2O )沉镍时,若PH值大于7.09,其产物为Ni3S2,若小于7.09,则产物为NiS2。
关键字: 镍 硫化物 沉淀 热力学
Pb IN PbSiF6-H2SiF6SYSTEM
(Institute for Environmental Protection, Hunan University, Changsha 410082)
Abstract:The influence of additive and technological parameter on cathode process of electrodepositing Pb in PbSiF6-H2SiF6electrolytic system was investigated by motional electric potential. The electrochemical mechanism of the process is indicated. The experimental results showed that controlling Pb in electrolyte as 40~120 g/L,H2SiF6as 90~120 g/L, sodium wood-sulfonate additive as 4 gL, high quality deposit Pb was obtained.
Key words: Pb H2SiF6 electrodeposition