H_3PO_4掺杂聚苯胺对碳钢的缓蚀性能研究

Research on Corrosion Inhibition of H_3PO_4 Doped PANi on Carbon Steel

金属管道、锅炉酸洗过程中,金属腐蚀不可避免,缓蚀剂是延缓金属腐蚀最有效、最经济的材料。苯胺低聚物具有可逆氧化还原特性,作为一种新型防腐蚀材料受到人们广泛关注。合成了一种水溶性良好的H_3PO_4掺杂聚苯胺纳米粒子缓蚀剂,采用动电位极化曲线和交流阻抗谱技术研究该缓蚀剂在1 mol/L HCl盐酸洗液中对碳钢的缓蚀性能和缓蚀机理,并结合扫描电镜和电子能谱分析碳钢腐蚀形貌和腐蚀产物成分。结果表明:H_3PO_4掺杂聚苯胺纳米粒子在碳钢表面吸附成膜,抑制氯离子对碳钢侵蚀,属于阳极型缓蚀剂。当缓蚀剂浓度为0.5 g/L时,120 min后的缓蚀效率高达94.9%。

During the acid pickling process of metal pipeline and boiler, the corrosion of metal is inevitable. Inhibitor is the most effective and economical way to decrease the corrosion rate of metal. Aniline oligomer possesses reversible redox performance, which enables them to be the new anticorrosion agents, and their anticorrosion performance has attracted intense attentions. Aniline oligomer is an important metal corrosion inhibitor. A water soluble inhibitor, H3 PO4 doped PANi nanoparticle, was synthesized by dispersion polymerization technology. The corrosion performance and corrosion mechanism of PANi nanoparticle on carbon steel in 1 mol/L HC1 were investigated by polarization curves and electrochemical impendence spectroscopy （EIS）. The corrosion product morphology and corrosion product components of carbon steel were also analyzed by electron scanning microscope（SEM） and energy dispersive spectroscopy （EDS）. Results indicated that H3PO4 doped PANi nanoparticle is an anodic corrosion inhibitor which formes a compact film on carbon steel surface and then inhibits the erosion of Cl-. When the concentration of inhibitor is 0. 5 g/L, its inhibition efficiency reaches 94. 9% after 120 min.