期刊名称:Journal of Materials and Environmental Science
印刷版ISSN:2028-2508
出版年度:2017
卷号:8
期号:7
页码:2455-2468
出版社:University of Mohammed Premier Oujda
摘要:The corrosion inhibition of mild steel in 1.0 M HCl solution by Alizarin was investigated using weight loss and electrochemical measurements. The results indicate that the studied compound exhibits good performance as inhibitor for mild steel corrosion in 1.0 M HCl solution and its inhibition efficiency increased with concentration to reach a maximum of 91 % at 10-3 M (optimum concentration). The potentiodynamic polarization curves showed that Alizarin acts as a cathodic type inhibitor. It is found also that the inhibition efficiency of this compound decreased with temperature to reach a minimum of 54.3 % at 10-3 M at 328 K. In the other, it is shown that the inhibition efficiency increased with immersion time until 4 h to get 0.89 % and decreased after this time to attain 66.1% at 12 h at the optimum concentration. So, the adsorption of Alizarin obeys to the Langmuir adsorption isotherm. In addition, the apparent activation energy, enthalpy, entropy and the free energy were determined and discussed. Finally, the quantum chemical parameters were determined using density functional theory (DFT) method to correlate the calculated structural and electronic parameters of Alizarin with its corrosion inhibition efficiency. The obtained results indicated a good agreement between experimental and theoretical studies.