用闭塞电池研究月桂酸根离子抑制碳钢垢下腐蚀的机理  

Under-deposit Occluded Cell Corrosion Inhibition Mechanism of N80 Steel in NaCl Solution Added with Sodium Laurate

作　　者：朱元良[1,2] 姬鄂豫[1] 邱于兵[2] 郭兴蓬[2] 

机构地区：[1]南阳理工学院生物与化学工程学院,南阳473066 [2]华中科技大学化学与化工学院,武汉430074

出　　处：《腐蚀与防护》2010年第2期111-114,共4页Corrosion & Protection

基　　金：河南省科技攻关项目(0524270015)

摘　　要：利用一种能够模拟局部腐蚀自催化过程的闭塞电池(OCC),通过耦合电流、极化电阻、电化学阻抗等,测量研究了月桂酸根离子(C_(12)H_(23)O_2^-)在中性NaCl溶液中对N80钢垢下闭塞区腐蚀行为的抑制机制。结果表明:C_(12)H_(23)O_2^-在碳钢表面吸附并通过垢层向闭塞区迁移,闭塞区内外电极极化电阻增大,腐蚀反应的阴阳极过程都受到抑制。C_(12)H_(23)O_2^-在垢层吸附,使垢层电阻增大,离子迁移阻力增大。这几种因素共同作用的结果抑制了闭塞区的腐蚀。Using a simulated occluded corrosion cell （OCC）, the inhibition mechanism of sodium laurate （C12H23O2 Na） preventing from the underdeposit occluded cell corrosion of N80 steel in 0. 2 mol/L NaCl solution was studied by electrochemical methods, including measurements of coupling currents, polarization resistance, electrochemical impedance spectroscopy（E/S）. The results showed that C12H23O2^- could migrate into the occluded cavity through the deposition and adsorption on the N80 steel surface in NaCl solution, which increased the polarization resistance of the occluded anode and the bulk cathode, obstructing both the anodic and cathodic processes. Due to the adsorption of C12H23O2^- on the deposited layer, the resistance of deposited layer increased markedly so as to prevent ions from migrating through the scale layer. All these effects resulted in inhibition of the underdeposit corrosion of N80 steel.

关 键 词：垢下腐蚀 闭塞腐蚀电池 碳钢 吸附 月桂酸盐 

分 类 号：TG174.42[金属学及工艺—金属表面处理] TG174.3[金属学及工艺—金属学]