Weight Loss, Thermodynamics, SEM, and Electrochemical Studies on N-2-Methylbenzylidene-4-antipyrineamine as an Inhibitor for Mild Steel Corrosion in Hydrochloric Acid

Abstract

The use of N-2-methylbenzylidene-4-antipyrineamine as an acid corrosion inhibitor for mild steel surfaces in hydrochloric acid is discussed in this article by means of weight loss, electrochemical impedance spectroscopy (EIS), and scanning electron microscopy (SEM) methods. The experimental findings exhibited that N-2-methylbenzylidene-4-antipyrineamine is a significant corrosion inhibitor for the mild steel in 1.0 M HCl solution and that its protection efficiency touches the peak at 5 × 10–4 M, exhibiting 91.8% for N-2-methylbenzylidene-4-antipyrineamine. The inhibitory efficiency increases as the inhibitor concentration rises and reduces as the temperature rises. Temperature has a significant impact on corrosion and blocking activities, which is extensively examined and explained. According to the gravimetric results, the examined inhibitor inhibits mild steel surface corrosion by providing a barrier at the metal–hydrochloric acid medium interface. Thermodynamic characteristics were combined with a quantum chemistry investigation using density functional theory to provide more insight into the inhibitory effect mechanism. The tested inhibitor adsorbs on the mild steel surface based on Langmuir’s adsorption isotherm method.

Keywords

• corrosion inhibitor
• antipyrineamine
• methylbenzylidene
• gravimetric
• EIS