月桂酸根离子吸附对碳钢表面垢层性质的影响  

Effect of Sodium Laurate on Characters of Deposits on Surface of N80 Steel in NaCl Solutions

作　　者：朱元良[1,2] 陈海玲[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：《腐蚀科学与防护技术》2010年第5期427-430,共4页Corrosion Science and Protection Technology

基　　金：河南省科技攻关项目(0524270015)资助

摘　　要：利用原子力显微镜成像技术和离子选择性测量研究了月桂酸根离子(C_(12)H_(23)O_2^-)对N80钢表面腐蚀垢层性质的影响.结果表明,C_(12)H_(23)O_2^-在表面垢层吸附并扩散进入垢下闭塞区,闭塞阳极表面粗糙度和相位对比度减小,腐蚀受到了抑制;C_(12)H_(23)O_2^-的吸附使垢层由阴离子选择性变为阳离子选择性,抑制Cl^-向闭塞区迁移,减弱了闭塞区的酸化自催化效应;C_(12)H_(23)O_2^-在垢层表面和垢内微孔定向排列,垢层由亲水性变为疏水性,离子迁移阻力增大.提出了垢层表面的物理模型,较好地解释了C_(12)H_(23)O_2^-的作用机制.The effect of sodium laurate on characters of deposits on the surface of N80 steel in NaCl solution was studied by means of atomic force microscopy（AFM） and ion-selectivity measurement of the deposits.The results showed that C_（12）H_（23）O_2^- could adsorb and migrate into the occluded cavity under the deposit in NaCl solution,therewith decreased the roughness and the phase contrast of the occluded anode surface,and inhibited the corrosion processes on it.C_（12）H_（23）O_2^- could change the deposit layer from anion selectivity to cation selectivity,which prevented Cl^- migrating into OCC,thereby inhibited the auto-catalyzing acidification effect in it.Meanwhile, a hydrophobic layer on the deposit surface could form through directional arrangement of alkyl chain by the adsorption of C_（12）H_（23）O_2^-,which might increase the resistance to ion migration through the deposit.A physical model was proposed to describe the surface of deposits to explain the mechanism of corrosion inhibition of C_（12）H_（23）O_2^- preferably.

关 键 词：腐蚀垢 闭塞腐蚀电池 吸附 离子选择性 润湿性 月桂酸根 

分 类 号：TG174.7[金属学及工艺—金属表面处理]