(1. 江西理工大学 冶金与化学工程学院，赣州 341000； 2. 中南大学 冶金与环境学院，长沙 410083)
摘 要: 对比研究锌电积电解液中氟、氯对Pb-Ag阳极恒流极化(500 A/cm2) 72 h后氧化膜层表面形貌、内部结构、物相组成和基底腐蚀的影响。结果表明：氟、氯抑制PbO2的生长，提高膜层中PbOn、PbO·PbSO4的含量。在含氟溶液中，氧化膜层表面呈鳞片状，内部孔洞、空隙增多，致密度降低；基底出现腐蚀孔洞，随着氟浓度增大，腐蚀孔洞增多、孔径增大、腐蚀深度变大。在含氯溶液中，氧化膜层表面呈胶结状，致密度与无氯电解液中的相当，但紧密层厚度明显减小；基底出现腐蚀坑，腐蚀深度小于含氟溶液中的。此外，分析了氟、氯对Pb-Ag阳极腐蚀行为的影响机制。氟主要通过降低氧化膜层致密度加剧Pb-Ag阳极的腐蚀，而氯主要通过减小氧化膜层厚度加剧阳极的腐蚀。
关键字: 锌电积；铅阳极；氟；氯；氧化膜层；腐蚀
（1. School of Metallurgical and Chemical Engineering, Jiangxi University of Science and Technology, Ganzhou 341000, China; 2. School of Metallurgy and Environment, Central South University, Changsha 410083, China）
Abstract:Effects of fluoride and chloride ions on surface morphology, inner structure, phase composition of anodic layer and substrate corrosion of Pb-Ag anode were comparatively investigated after 72 h galvanostatic electrolysis (500 A/cm2) in zinc electrolyte. The results show that both fluoride and chloride ions inhibite the growth of PbO2 in anodic layer, and increase the concentration of PbOn and PbO·PbSO4. In the presence of fluoride ion, anodic layer surface presents scale-like morphology, the inner part of anodic layer shows lower compactness with large numbers of holes and crevices. As fluoride ion concentration ascended, the number and diameter of corrosion holes presented on the metallic substrate increase, and the corrosion depth increases. In the presence of chloride ion, anodic layer surface shows the cement structure, the inner compactness is similar with that in H2SO4 solution without chloride ion, while the thickness of compact layer decreases largely. Metallic substrate shows the corrosion pits, and the corrosion depth is smaller than that in fluoride ion containing electrolyte. Furthermore, the influence mechanism of fluoride and chloride ions on corrosion behavior of Pb-Ag anode is analyzed. Fluoride ion accelerates the corrosion of metallic substrate through decreasing compactness of anodic layer, while chloride ion deteriorates the corrosion of Pb-Ag anode mainly through decreasing the thickness of anodic layer, especially the thickness of inner compact layer.
Key words: zinc electrowinning; lead anode; fluoride; chloride; anodic layer; corrosion
