Abdallah M, Soliman K A, Al-Gorair Arej S, Al Bahir A, Al-Fahemi Jabir H, Motawea M S, Al-Juaid Salih S
Chemistry Department, Faculty of Applied Science, Umm Al-Qura University Makkah Saudi Arabia
Chemistry Department, Faculty of Science, Benha University Benha Egypt.
RSC Adv. 2021 May 11;11(28):17092-17107. doi: 10.1039/d1ra01010g. eCollection 2021 May 6.
The inhibition potency of expired thiamine or vitamin B1 (VB1) and riboflavin or vitamin B2 (VB2) against SABIC iron corrosion in 0.5 M HSO solutions was investigated using chemical and electrochemical techniques. Theoretical studies such as DFT and MC simulations were performed on both VB1 and VB2 inhibitors to obtain information related to the experimental results. It has been found that the inhibition efficacy assigned from all measurements used increases with increasing concentration of the two expired vitamins and reduces at elevated temperatures. It reached 91.14% and 92.40% at 250 ppm of VB1 and VB2, respectively. The inhibition was explicated by the adsorption of the complex formed between expired vitamins and ferrous ions on the SABIC iron surface. The adsorption was found to obey the Langmuir isotherm model. Galvanostatic polarization demonstrated that the two expired vitamins act as an inhibitor of the mixed type. These expired vitamins have proven effective in inhibiting the pitting corrosion induced by the presence of Cl ions. The pitting potential is transferred to the positive values showing resistance to pitting damage. The theoretical parameter values are consistent with experimental results.
采用化学和电化学技术研究了过期硫胺素或维生素B1（VB1）以及核黄素或维生素B2（VB2）在0.5 M HSO溶液中对沙特基础工业公司（SABIC）铁腐蚀的抑制效能。对VB1和VB2抑制剂进行了密度泛函理论（DFT）和蒙特卡罗（MC）模拟等理论研究，以获取与实验结果相关的信息。结果发现，所有测量得出的抑制效率随着两种过期维生素浓度的增加而提高，在温度升高时降低。在VB1和VB2浓度为250 ppm时，抑制效率分别达到91.14%和92.40%。过期维生素与亚铁离子形成的络合物在SABIC铁表面的吸附解释了这种抑制作用。发现该吸附服从朗缪尔等温线模型。恒电流极化表明这两种过期维生素起到混合型抑制剂的作用。这些过期维生素已被证明能有效抑制由Cl离子存在引起的点蚀。点蚀电位转移到正值，表明对点蚀破坏具有抗性。理论参数值与实验结果一致。
