Electrochemical Corrosion Performance of N80 steel in Acidized 10% HCl medium using 4-methyl-1-Phenyl-3-(p-tolyldiazenyl) −2,3-dihydro-1H-pyrrol-2-ol

Abstract

<h2>Abstract</h2><h3>Background</h3> In this study, the azo dye, 4-methyl-1-phenyl-3-(p-tolyldiazenyl)-2,3-dihydro-1H-pyrrol-2-ol <b>(MPTHP)</b> was synthesized and estimated as a novel inhibitor for protecting N80 steel from corrosion in a 10 % HCl acidic environment. <h3>Methods</h3> Potentiodynamic polarization (PP) and electrochemical impedance spectroscopy (EIS) methods were employed. Additionally, Monte Carlo (MC) simulations and density functional theory (DFT) were utilized to establish a link between the protective capacity and the molecular structure of the inhibitor. <h3>Significant findings</h3> The inhibitor confirmed an impressive inhibition prohibition of 91 % when its concentration was increased to 1 × 10⁻⁴ M at 25 ± 1 °C, as determined by EIS analysis. PP analysis indicated that the MPTHP azo-dye compound functions as a mixed-type inhibitor and chemisorbs onto the surface of N80 steel. Furthermore, the Langmuir adsorption isotherm was found to be the most suitable model to describe the adsorption of the examined compound. This research has the potential to introduce MPTHP as an innovative corrosion inhibitor for preventing N80 steel corrosion in various industrial settings, particularly in pickling solutions.