木质素磺酸钠在混凝土模拟孔隙液中对碳钢的缓蚀与吸附作用  

Inhibition Action and Adsorption Behavior of Sodium Lignosulphonate on Q235 Steel in Simulated Concrete Solution

作　　者：谢婉晨 李建三[1] XIE Wanchen;LI Jiansan(College of Mechanical and Automobile Engineering,South China University of Technology,Guangzhou 510640)

机构地区：[1]华南理工大学机械与汽车工程学院,广州510640

出　　处：《材料导报》2019年第8期1401-1405,共5页Materials Reports

摘　　要：本实验采用动电位极化、表面形貌分析等方法研究了木质素磺酸钠在含氯混凝土模拟孔隙液中对碳钢的缓蚀性能,探讨了吸附行为。结果表明,木质素磺酸钠在混凝土模拟孔隙液体系中对碳钢有较好的抗点蚀缓蚀性能,缓蚀效果随木质素磺酸钠添加量的增加而增强。木质素磺酸钠在碳钢表面的吸附过程是自发放热反应,随温度升高,其对碳钢的缓蚀作用降低。吸附行为符合Langmuir吸附等温式,属于以化学吸附为主的混合吸附。其中磺酸基与Ca^(2+)之间的共吸附作用为物理吸附,羧基、苯环结构与Fe的3d空轨道发生配位形成配位键,为化学吸附。木质素磺酸钠形成均匀的吸附膜能有效减少Cl-在钝化膜表面的特性吸附,有效抑制Cl-引起的碳钢点蚀。Inhibition action and adsorption behavior of sodium lignosulphonate on Q235 steel in simulated concrete solution were investigated by means of potentiodynamic polarization and surface analysis techniques.The results indicated that sodium lignosulphonate have good pitting corrosion inhibition for Q235 steel in simulated concrete solution.The inhibition efficiency strengthened with increase of sodium lignosulphonate concentration.The adsorption reaction was a spontaneous exothermic process and followed Langmuir isotherm.It belonged to mix-type adsorption mainly dominated by chemisorption.The coadsorption of sulfonic acid group and Ca^2+belonged to physisorption.Carboxyl and benzene ring structure had coordinated with Fe-3d orbitals,which belonged to chemisorption.Adsorption film of sodium lignosulphonate formed on Q235 steel can reduce adsorption of Cl^-so pitting corrosion caused by Cl^-can be effectively suppressed.

关 键 词：木质素磺酸钠 碳钢 缓蚀性能 吸附等温式 

分 类 号：TG174.2[金属学及工艺—金属表面处理]