Synergic Mechanism of an Organic Corrosion Inhibitor for Preventing Carbon Steel Corrosion in Chloride Solution

• Published in: Journal of Wuhan University of Technology. Materials science edition Vol. 30; no. 2; pp. 325 - 330
• Main Author: 刘志勇 YU Lei LI Qingzhong
• Format: Journal Article
• Language: English
• Published: Heidelberg Wuhan University of Technology 01-04-2015; Springer Nature B.V
• Subjects: Advanced Materials; Carboxylic acids; Chemistry and Materials Science; Chlorides; Computational efficiency; Computing time; Corrosion inhibitors; Inhibition; Inhibitors; Materials Science; Quantum chemistry; 二甲基乙醇胺; 协同机制; 有机抑制剂; 有机缓蚀剂; 氯化物溶液; 碳钢腐蚀; 量子化学计算; 预防; inhibition; organic corrosion inhibitor; polarization; chloride solution; carbon steel
• ISSN: 1000-2413; 1993-0437
• DOI: 10.1007/s11595-015-1148-z

The inhibition effect of dimethylethanolamine（DMEA） and its composite with carboxylic acid was studied with the electrochemical tests. The experimental results indicate that DMEA is not a good inhibitor but the composite of DMEA with caprylic acid exhibits excellent inhibiting efficiency. The synergic mechanism of the organic corrosion inhibitors（OCIs） was studied with quantum chemical calculations. It is found that the DMEA forms a quaternary ammonium salt with the proton in carboxylic acid, and a cyclic complex formed between the salt and Fe may be responsible for the enhancement of inhibiting efficiency. The possible hydrogen bond formed between DMEA and carboxylic acid is not enough for the inhibiting effect. This work is helpful to proposing theoretical interpretation as well as developing a functional organic inhibitor to improve the durability of reinforced concrete contaminated with chloride.