Department of Chemical and Process Engineering, Faculty of Engineering and Built Environment, Universiti Kebangsaan Malaysia, Bangi, Malaysia.
University of Technology-Iraq, Energy and Renewable Energies Technology Center, Bagdad, Iraq.
Sci Rep. 2023 Jun 16;13(1):9770. doi: 10.1038/s41598-023-36252-8.
The corrosion inhibition properties of 2-(1,3,4-thiadiazole-2-yl)pyrrolidine (2-TP) on mild steel in a 1 M HCl solution were investigated using weight loss, potentiodynamic polarization, electrochemical impedance spectroscopy (EIS) and open circuit potential (OCP) measurements. In addition, DFT calculations were performed on 2-TP. The polarization curves revealed that 2-TP is a mixed-type inhibitor. The results indicate that 2-TP is an effective inhibitor for mild steel corrosion in a 1.0 M HCl solution, with an inhibition efficiency of 94.6% at 0.5 mM 2-TP. The study also examined the impact of temperature, revealing that the inhibition efficiency increases with an increasing concentration of 2-TP and decreases with a rise in temperature. The adsorption of the inhibitor on the mild steel surface followed the Langmuir adsorption isotherm, and the free energy value indicated that the adsorption of 2-TP is a spontaneous process that involves both physical and chemical adsorption mechanisms. The DFT calculations showed that the adsorption of 2-TP on the mild steel surface is mainly through the interaction of the lone pair of electrons on the nitrogen atom of the thiadiazole ring with the metal surface. The results obtained from the weight loss, potentiodynamic polarization, EIS and OCP measurements were in good agreement with each other and confirmed the effectiveness of 2-TP as a corrosion inhibitor for mild steel in 1.0 M HCl solution. Overall, the study demonstrates the potential use of 2-TP as a corrosion inhibitor in acid environments.
2-(1,3,4-噻二唑-2-基)吡咯烷（2-TP）在 1M HCl 溶液中对低碳钢的缓蚀性能采用失重法、动电位极化、电化学阻抗谱（EIS）和开路电位（OCP）测量进行了研究。此外，还对 2-TP 进行了 DFT 计算。极化曲线表明 2-TP 是一种混合型抑制剂。结果表明，2-TP 是 1.0M HCl 溶液中低碳钢腐蚀的有效抑制剂，在 0.5mM 2-TP 时抑制效率为 94.6%。研究还考察了温度的影响，结果表明随着 2-TP 浓度的增加，抑制效率增加，而随着温度的升高，抑制效率降低。抑制剂在低碳钢表面的吸附遵循 Langmuir 吸附等温线，自由能值表明 2-TP 的吸附是一个自发过程，涉及物理和化学吸附机制。DFT 计算表明，2-TP 在低碳钢表面的吸附主要是通过噻二唑环上氮原子的孤对电子与金属表面的相互作用。失重法、动电位极化、EIS 和 OCP 测量得到的结果相互吻合，证实了 2-TP 作为 1.0M HCl 溶液中低碳钢缓蚀剂的有效性。总的来说，该研究表明 2-TP 作为一种在酸性环境中使用的缓蚀剂具有潜在的应用价值。
