Experimental and Theoretical Tests on the Corrosion Protection of Mild Steel in Hydrochloric Acid Environment by the Use of Pyrazole Derivative

• Published in: Materials 2023-01, Vol.16 (2), p.678
• Main Authors: Boudalia, Maria, Fernández-Domene, R M, Guo, L, Echihi, S, Belghiti, M E, Zarrouk, A, Bellaouchou, A, Guenbour, A, García-Antón, J
• Format: Article
• Language: English
• Subjects: Adsorption; Barrier layers; Cathodic protection; Charge transfer; Corrosion; Corrosion inhibitors; Corrosion mechanisms; Corrosion prevention; Corrosion resistance; Corrosion tests; Efficiency; Electrochemical impedance spectroscopy; Hydrochloric acid; Low carbon steels; Metals; Monte Carlo simulation; Polarization; Pyrazole; Steel alloys; Steel pipes; Surface chemistry; Weight loss measurement
• ISSN: 1996-1944; 1996-1944
• DOI: 10.3390/ma16020678

In this study, 1,5-diallyl-1H-pyrazolo [3,4-d] pyrimidin-4 (5H)-one (PPD) was evaluated as an anticorrosion agent for mild steel (MS) in 1 M HCl. The analysis was performed by weight loss (WL), potentiodynamic polarization measurement, and electrochemical impedance spectroscopy (EIS). The Tafel polarization showed that PPD is a mixed-type inhibitor and reaches 94% of the protective efficiency at 10 M. EIS results indicated that the resistance to charge transfer increases with increasing inhibitor concentration and the corrosion of MS is controlled by a charge transfer process. The inhibitor adsorption on the MS surface obeyed the Langmuir's adsorption isotherm. Thermodynamic parameters were calculated to elaborate the corrosion inhibition mechanism. The micrographic analysis revealed the existence of a barrier layer on the electrode surface with the presence of PPD. Theoretical examinations performed by electronic/atomic computer simulations confirmed that the obtained results were found to be consistent with experimental findings.