碳钢在含热稳定性盐的N-甲基二乙醇胺介质中的腐蚀行为  

CORROSION BEHAVIOR OF CARBON STEEL IN METHYLDIETHANOLAMINE SOLUTION CONTAINING HEAT-STABLE SALTS

作　　者：韦冬萍[1,2] 胡荣宗[1] 潘丹梅[1] 黄维雄[1] 董瑞[1] 

机构地区：[1]厦门大学化学化工学院化学系,现代分析科学教育部重点实验室,厦门361005 [2]广西民族大学化学与生态工程学院,南宁530006

出　　处：《腐蚀科学与防护技术》2008年第5期331-335,共5页Corrosion Science and Protection Technology

基　　金：国家自然科学基金项目(20527005)资助

摘　　要：利用阳极极化曲线法、Tafel曲线法和电化学阻抗谱法等技术,研究含有各种模拟热稳定性盐(HSS)的N-甲基二乙醇胺(MDEA)溶液在含氧与除氧条件下以及不同温度下对碳钢的腐蚀行为.结果表明,HSS的存在使碳钢的腐蚀速度加快.常温下HSS中的Cl-对碳钢的腐蚀性最强、可导致碳钢发生孔蚀;溶解氧的存在有利于降低既定HSS的腐蚀性.温度升高,碳钢的全面腐蚀速度增加,宏观孔蚀受到抑制;在含HSS的MDEA溶液中,碳钢腐蚀反应的阴极过程为电化学反应和扩散传质混合控制,阳极过程为电化学反应控制.In the present work,30 mass% methyldiethanolamine（MDEA） solutions containing various simulated heat-stable salts （HSS） were prepared. The corrosion behavior and the relevant corrosion rate-determining factors of carbon steel in the solutions were investigated by anodic polarization curve, Tafel curve and electrochemical impedance spectroscopy. It was showed that the corrosion rate of carbon steel in MDEA solution with HSS was double higher than that without HSS. Carbon steel might suffer from pitting corrosion in MDEA solutions containing chloride ions at ambient temperature. The corrosion rate of carbon steel in the solutions could be decreased when dissolved oxygen was existent. The general corrosion rate was increased as well as the pitting corrosion was inhibited at high temperatures. The rate of cathodic reduction was determined by both the electrochemical reaction and the diffusion process in MDEA solution with HSS. The rate-determining step of the anodic dissolution was electrochemical reaction in MDEA solution with HSS.

关 键 词：热稳定性盐 N-甲基二乙醇胺 碳钢 腐蚀 Tafel曲线 电化学阻抗谱 

分 类 号：TG172.62[金属学及工艺—金属表面处理]