Monitoring the Interaction of Two Heterocyclic Compounds on Carbon Steel by Electrochemical Polarization, Noise, and Quantum Chemical Studies

Abstract

A heterocyclic phenylhydrazone 2-[(E)-(2-phenylhydrazinylidene)methyl]pyridine (P2APH) and its reduced form 2-[(2-phenylhydrazinyl)methyl]pyridine (RP2APH) were synthesized, characterized, and subjected to corrosion inhibition investigation on carbon steel (CS) in 1 M HCl using gravimetric, polarization, electrochemical noise, quantum chemical, and surface studies. P2APH showed more inhibition capacity than RP2PPH. But RP2PPH was very stable in acid medium and showed pronounced corrosion inhibition efficacy for days. Energy of HOMO and LUMO, their difference, number of electrons transferred, electronegativity, chemical hardness, and so forth were evaluated by quantum chemical studies. Agreeable correlation was observed between the results of quantum chemical calculations and other corrosion monitoring techniques.

Synthesis, Cyclic Voltammetric, Electrochemical, and Gravimetric Corrosion Inhibition Investigations of Schiff Base Derived from 5,5-Dimethyl-1,3-cyclohexanedione and 2-Aminophenol on Mild Steel in 1 M HCl and 0.5 M H2SO4

“…However they easily undergo acid attack and get corroded. Acid solutions are commonly used in industries for various cleaning processes [5][6][7][8]. Corrosion inhibition using inhibitors is a developing field in chemistry.…”

Anti-metal Deteriorating and Antiviral Potency of a Novel Polynuclear Schiff base Derived from Anthrone

“…Various adsorption isotherms were drawn and the isotherm with a straight line and correlation coefficient (R 2 ) very close to unity is considered as the best fitted adsorption isotherm. Among the isotherms studied, Langmuir adsorption isotherm was best suited and the model is represented as 39 Langmuir adsorption isotherm = (5)…”

“…Quantum chemical parameters help to calculate the number of electrons (ΔN) transferred from the ANHIS to the CS surface. For a bulk Iron metal, chemical hardness and the electronegativity are taken as zero and 7eV respectively for the easiness of calculation 39 .…”

“…In metallic corrosion (acidic medium), the inhibitor (soft base) is more efficient since bulk metals are soft acids. Soft molecules generally have a small value of chemical hardness, low energy gap of HOMO-LUMO, and enhanced polarizability 39 . Usually they may have high chemical reactivity.…”