Center of Research Excellence in Corrosion, Research Institute, King Fahd University of Petroleum and Minerals, Dhahran, 31261, Saudi Arabia.
Department of Chemistry, Edo University, Iyamho, Edo State, Nigeria.
Carbohydr Polym. 2017 Dec 15;178:200-208. doi: 10.1016/j.carbpol.2017.09.049. Epub 2017 Sep 14.
Sodium alginate (SA), a polysaccharide biopolymer, has been studied as an effective inhibitor against the corrosion of API X60 steel in neutral 3.5% NaCl using gravimetric and electrochemical techniques (OCP, EIS and EFM). The inhibition efficiency of the SA increased with concentration but was lower at higher temperature (70°C). Electrochemical measurements showed that the SA shifted the steel corrosion potential to more positive value and reduced the kinetics of corrosion by forming an adsorbed layer which mitigated the steel surface wetting, based on contact angle measurement. SEM-EDAX was used to confirm the inhibition of SA on API X60 steel surfaces. The SA adsorbs on the steel surface through a physisorption mechanism using its carboxylate oxygen according to UV-vis and ATR-IR measurements, respectively. This phenomena result in decreased localized pitting corrosion of the API X60 steel in 3.5% NaCl solution. Theoretical results using quantum chemical calculations and Monte Carlo simulations provide further atomic level insights into the interaction of SA with steel surface.
海藻酸钠（SA）是一种多糖生物聚合物，已被研究为在中性 3.5%NaCl 中有效抑制 API X60 钢腐蚀的抑制剂，使用重量法和电化学技术（OCP、EIS 和 EFM）。SA 的抑制效率随浓度增加而增加，但在较高温度（70°C）下较低。电化学测量表明，SA 通过形成吸附层将钢的腐蚀电位移向更正值，并通过减缓钢表面润湿来降低腐蚀动力学，基于接触角测量。SEM-EDAX 用于确认 SA 对 API X60 钢表面的抑制作用。SA 通过其羧酸盐氧根据 UV-vis 和 ATR-IR 测量分别通过物理吸附机制吸附在钢表面上。这种现象导致 API X60 钢在 3.5%NaCl 溶液中局部点蚀腐蚀减少。使用量子化学计算和蒙特卡罗模拟的理论结果提供了对 SA 与钢表面相互作用的进一步原子水平的见解。
