Experimental and Quantum Chemical Investigations on the Anticorrosion Efficiency of a Nicotinehydrazide Derivative for Mild Steel in HCl

Abstract

A corrosion inhibitor namely N′-(4-hydroxy-3-methoxybenzylidene) nicotinohydrazide was synthesized and the inhibition efficiency of the investigated inhibitor toward the mild steel corrosion in 1 M HCl was studied. The anticorrosion effect has been investigated by weight loss (WL) techniques and electrochemical analysis includes potentiodynamic polarization (PDP) studies and electrochemical impedance spectroscopy (EIS). The current investigation has demonstrated that the tested inhibitor is suitable in corrosive environment and the inhibitive efficacy up to 97% in 1 M HCl. PDP measurements showed that the nicotinohydrazide is a mixed type inhibitor. EIS measurements showed that an increase in the inhibitory concentration leads to an increase in the charge transfer resistance (Rct) and a decrease in the double-layer capacitance (Cdl). Experimental results for the inhibitory performance of WL methods and electrochemical techniques (PDP and EIS) are in good agreement. The tested inhibitor molecules adsorbed on the surface of mild steel in a hydrochloric acid solution followed Langmuir’s isothermal adsorption. Quantum chemical parameters based on density function theory (DFT) techniques were conducted on oxygen/nitrogen-bearing heterocyclic molecule employed as a corrosion inhibitor for mild steel in HCl to evaluate the correlation between the inhibitor structure and inhibitory performance. The parameters including the energy gap (ΔE), dipole moment (μ), electronegativity (χ), electron affinity (A), global hardness (η), softness (σ), ionization potential (I), the fraction of electrons transferred (ΔN), the highest occupied molecular orbital energy (EHOMO), and the lowest unoccupied molecular orbital energy (ELUMO) were also calculated and were in good agreement with the experimental results.

A combined experimental and theoretical study of a novel corrosion inhibitor derived from thiophen

“…The corrosion rate of a metallic substrate in a corrosive environment is governed by two primary processes: the hydrogen evolution reaction and the iron dissolution reaction. These mechanisms are elucidated by Equations (14)–(15), [ 56 ] delineating the steps involved in the anodic breakdown of iron: $$$\mathrm{Fe}+{\mathrm{Cl}}^{-}\leftrightarrow {({\mathrm{FeCl}}^{-})}_{\mathrm{ads}},$$$ $$${({\mathrm{FeCl}}^{-})}_{\mathrm{ads}}\leftrightarrow {(\mathrm{FeCl})}_{\mathrm{ads}}+{{\rm{e}}}^{-},$$$ $$${(\mathrm{FeCl})}_{\mathrm{ads}}\to {({\mathrm{FeCl}}^{+})}_{\mathrm{ads}}+{{\rm{e}}}^{-},$$$ $$${({\mathrm{FeCl}}^{+})}_{\mathrm{ads}}\to {\mathrm{Fe}}^{++}+{\mathrm{Cl}}^{-}.$$$…”

“…The corrosion rate of a metallic substrate in a corrosive environment is governed by two primary processes: the hydrogen evolution reaction and the iron dissolution reaction. These mechanisms are elucidated by Equations ( 14)-( 15), [56] delineating the steps involved in the anodic breakdown of iron:…”

Experimental and Theoretical investigations of the Inhibition of the Corrosion of Mild Steel in HCl by Synthesized Piperazin Derivatives

“…We denote the electron transfer from the inhibitor to the metal as (𝑁 𝑖𝑛ℎ−𝑀𝑆 ) and the reverse by (𝑁 𝑀𝑆−𝑖𝑛ℎ ). Consequently, inhibition exhinited a rise with an increase in 𝑁 𝑖𝑛ℎ−𝑀𝑆 (Betti et al, 2022) and can be more stabilized if the two are involved.…”

Exploring corrosion protection for mild steel in HCl solution: An experimental and theoretical analysis of an antipyrine derivative as an anticorrosion agent

“…[ 16,17 ] Enter corrosion inhibitors—compounds designed to curtail or prevent metal corrosion by establishing a protective film on the metal surface, effectively barricading corrosive agents from the metal's vulnerable structure. [ 18 ] These inhibitors can be categorized into organic and inorganic varieties, depending on their chemical composition. While inorganic inhibitors like chromates and phosphates have seen widespread use across industries, [ 19,20 ] mounting concerns regarding toxicity and environmental impacts have spurred increased interest in the development of organic alternatives.…”