Theoretical and electrochemical evaluation of tetra-cationic surfactant as corrosion inhibitor for carbon steel in 1 M HCl

A Elaraby; Shrouk Abd El-Samad; Eman A Khamis; E G Zaki

doi:10.1038/s41598-023-27513-7

Theoretical and electrochemical evaluation of tetra-cationic surfactant as corrosion inhibitor for carbon steel in 1 M HCl

Sci Rep. 2023 Jan 18;13(1):942. doi: 10.1038/s41598-023-27513-7.

Authors

A Elaraby¹, Shrouk Abd El-Samad², Eman A Khamis^{2

3}, E G Zaki⁴

Affiliations

¹ Egyptian Petroleum Research Institute, Nasr City 11727, Cairo, Egypt. a_elaraby19@yahoo.com.
² Egyptian Petroleum Research Institute, Nasr City 11727, Cairo, Egypt.
³ University College of Umluj, University of Tabuk, Tabuk, Saudi Arabia.
⁴ Egyptian Petroleum Research Institute, Nasr City 11727, Cairo, Egypt. elsyedzaki17@epri.sci.eg.

Abstract

Recently, scientist study the role of surfactants for carbon steel corrosion protection. In the present study, newly tetra-cationic surfactant (CS4: 1,N1'-(ethane-1,2-diyl) bis (N1, N2-didodecyl-N2-(2- (((E)-3-hydroxy-4-methoxy-benzylidene)amino)ethyl)ethane-1,2-diaminium) chloride) based on Schiff-base compound(5,5'-((1E,17E)-2,5,8,11,14,17-hexaazaoctadeca-1,17-diene-1,18-diyl)bis(2-methoxyphenol) was synthesised, purified and characterized using FTIR and ¹HNMR spectroscopy. The synthesized Tetra-cationic surfactant (CS4) was evaluated as anti-corrosion for carbon steel (CS-metal) in aggressive 1 M HCl using electrochemical impedance spectroscopy (EIS) and potentiodynamic polarization techniques (PDP). CS4 compound had a good surface-active property by reducing the surface tension as a result to the hydrophobic chains role. The prepared CS4 behaved as hybrid inhibitor (mixed-type) by blocking the anodic and cathodic sites. CS4 exhibited good inhibition efficiency reached 95.69%. The surface morphology of CS-metal was studied using scanning electron microscopy (SEM) and X-ray photoelectron spectroscopy (XPS)confirming the anti-corrosive effect of CS4 compound returned into the adsorption process of CS4 molecules over CS-metal which obeyed Langmuir adsorption isotherm. The inhibitive effect of CS4 was supported by theoretical quantum chemical studies using the density functional theory (DFT), Monte Carlo (MC) and Molecular Dynamic (MD) simulation.