硫酸铁溶液中方铅矿溶解的混合电位振荡现象

来源期刊：中南大学学报(自然科学版)2006年第3期

论文作者：周丽 李和平 徐丽萍

文章页码：579 - 582

关键词：振荡反应;方铅矿;氧化溶解;混合电位

Key words：oscillation reaction; galena; oxidative dissolution; mixed potentia

摘    要：通过动态测量混合电位,研究方铅矿电极在不同浓度的硫酸铁溶液中溶解的动力学过程。实验结果表明:在35℃的0.10和0.01 mol/L的Fe₂(SO₄)₃溶液中,方铅矿的溶解存在电化学振荡现象,方铅矿电极的混合电位随时间发生有规律的波动;开放体系下由溶解氧驱动的方铅矿表面Fe³⁺浓度的周期变化、方铅矿电极表面单质硫的生成及其进一步氧化溶解、以及已反应方铅矿表面的缺陷层的重新生成和再分解,都将影响每个电极反应的中间步骤,所有这些因素的耦合和反馈,将会导致硫酸铁溶液中方铅矿混合电位的振荡变化。

Abstract: The kinetics of the dissolution of galena was investigated by monitoring the mixed potential of galena electrode in ferric sulfate solutions. The results show that the mixed potential of galena electrode oscillates with time regularly in 0.10 and 0.01 mol/L Fe₂(SO₄)₃solutions at 35℃. The periodic variation of the concentration of Fe³⁺ on galena surface driven by dissolved oxygen in an open system, the formation of sulfur and its further oxidative dissolution on the galena electrode surface, and the recurring development and decomposition of the defective layers on reacted galena surface will affect each corresponding intermediate process. The coupling and feedback of all these factors can result in the oscillation of mixed potential of galena electrode in ferric sulfate solutions.