电化学除盐过程中钢筋表面发生的电极反应  

ELECTRODE REACTION DURING ELECTROCHEMICAL CHLORIDE EXTRACTION OF REINFORCED CONCRETE

作　　者：郑靓[1,2] 韦江雄[1,2] 余其俊[1,2] 杨墨[1,2] 邓春林[1,2] 王新祥[1,3] 

机构地区：[1]华南理工大学材料科学与工程学院,广州510640 [2]特种功能材料教育部重点实验室华南理工大学,广州510640 [3]广东省建筑科学研究院,广州510500

出　　处：《硅酸盐学报》2009年第7期1190-1195,共6页Journal of The Chinese Ceramic Society

基　　金：国家自然科学基金(50602016)资助项目

摘　　要：对氯盐污染混凝土进行电化学除盐时阴极附近产生的气体进行收集与分析,研究了电化学除盐时钢筋表面发生的电极反应。结果表明:在电化学除盐前期钢筋表面析氢和耗氧反应同时存在,在氧气消耗到一定程度后,电极反应主要为析氢反应。析氢反应主要取决于电流密度,氢气的生成常数kH2与电流密度I存在线性关系kH2=5.36×10–8I–1.99×10–8;耗氧反应则在除盐早期决定于电流密度,而后期则取决于O2扩散到混凝土表面的速率。By collection and analysis of the gas formed in the vicinity of the cathode, the electrode reaction on the steel surface of reinforcement material during electrochemical chloride extraction （ECE） was studied. The results show that hydrogen gas evolution reaction and oxygen gas consumption reaction occur on the surface of the reinforcement material during the early stage of ECE, and the hydrogen gas evolution reaction becomes dominant when oxygen gas is consumed to some extent. The hydrogen gas evolution reaction is mainly dependent on the electrical current density, and the constant of hydrogen gas generation kH2 has a linear relationship with electrical current density I as κH2=5.36×10^-8 I-1.99×10^-8. The oxygen gas consumption reaction is greatly varies with electrical current density during the early stage of ECE, and with the diffusion rate of oxygen gas towards the surface of concrete during the late stage of ECE.

关 键 词：电化学除盐 电极反应 析氢反应 耗氧反应 扩散 

分 类 号：TV431[水利工程—水工结构工程]