Corrosion Inhibition of Mild Steel in 1.0 M HCl Solution by Amine Derivatives

Abstract

This study explores the efficacy of amine derivatives (aniline and n-butylamine) in preventing corrosion of mild steel in a 1.0 M HCl solution. Employing a combination of potentiodynamic polarization techniques and electrochemical impedance spectroscopy (EIS), the study assesses the corrosion process. Furthermore, scanning electron microscopy (SEM) was used to analyze the changes in the surface morphology of mild steel in the presence of amine derivatives, while UV-visible spectroscopy (UV-Vis) and Fourier-transform infrared spectroscopy (FTIR) provided additional insights into the protective mechanisms at play. The results indicated that derivatives achieved inhibition efficiencies of 85.96% and 67.39%, respectively. The inclusion of a nitrogen atom in the amine structure enhanced the performance of these inhibitors. FTIR-ATR spectra revealed the N-H stretching, which is the indicative of amine groups reacting with the acid and metal surface to form protective films, thereby inhibiting corrosion. UV-Vis spectroscopy has confirmed the formation of a complex between Fe²⁺/Fe³⁺ ions and the inhibitors, corroborating the corrosion inhibition observed. The SEM analysis confirmed that the inhibitors effectively enhanced the condition of the mild steel surface in comparison to the untreated samples demonstrating their ability to make a significant impact and extend the lifespan and durability of steel structures in the corrosive environments.