咪唑啉与硫脲在CO_2腐蚀体系中的缓蚀协同作用机理  

Synergistic Inhibition Mechanism of Imidazoline and Thiourea in CO_2 Corrosive System

作　　者：赵景茂[1] 陈国浩[1] 

机构地区：[1]北京化工大学材料科学与工程学院,北京100029

出　　处：《中国腐蚀与防护学报》2013年第3期226-230,共5页Journal of Chinese Society For Corrosion and Protection

基　　金：国家自然科学基金资助项目(51171013)

摘　　要：采用极化曲线和电化学阻抗技术(EIS)研究了油酸基咪唑啉季铵盐(OIMQ)与硫脲(TU)对Q235碳钢在CO2饱和盐水溶液中的缓蚀协同效应。结果表明,TU对碳钢腐蚀的阴极过程和阳极过程都有强烈的抑制作用,而OIMQ是一种以抑制阳极为主的混合型缓蚀剂。二者复配使用,可以有效降低使用浓度,表现出优异的缓蚀协同效应。OIMQ与TU在碳钢表面形成了一层双层结构的缓蚀剂吸附膜,TU可能主要存在于膜的底部,而OIMQ主要存在于膜的顶部,这种结构的缓蚀剂膜一方面阻止了腐蚀性离子的渗透,另一方面也限制了TU分子的脱附。The synergistic inhibition effect between oleic-based imidazoline quaternary ammonium salt （OIMQ） and thiourea （TU） for Q235 carbon steel in CO2-saturated brine solution was investigated by using polarization curves and electrochemical impedance spectroscopy （EIS）. The results showed that TU had strong inhibition on the anodic and cathodic processes of carbon steel corrosion, while OIMQ acted as mixed-type inhibitor preferentially restraining the anodic process of metal. The combination of OIMQ and TU could effectively decrease the additive concentration and showed excellent synergistic inhibition effect. A hi-layer inhibitor film with the inner layer of TU molecules and the outer layer of imidazoline molecules was formed, which could retard the desorption of TU molecules and the attack of aggressive ions.

关 键 词：缓蚀剂 协同效应 咪唑啉 硫脲 CO2腐蚀 

分 类 号：TG174.42[金属学及工艺—金属表面处理]