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Gravimetric Measurements and Theoretical Calculations of 4-Aminoantipyrine Derivatives as Corrosion Inhibitors for Mild Steel in Hydrochloric Acid Solution: Comparative Studies

A. A. H. Kadhum|Firas F. Sayyid|Ali M. Mustafa|Slafa I. Ibrahim|Mustafa K. Mohsin|Mahdi M. Hanoon|Mohammed H. H. Al-Kaabi|Wan Nor Roslam Wan Isahak|A. A. Al-Amiery
한국재료부식학회 (The Corrosion Science Society of Korea)|2023.04|CORROSION SCIENCE AND TECHNOLOGY|제22권 제2호|pp. 73-89|DOI 10.14773/cst.2023.22.73

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키워드

Corrosion inhibitorPyridine4-AminoantipyrineFuranGravimetric
주제분류금속공학

초록

Due to continuous promotion of green alternatives to toxic petrochemicals by government policies,research efforts towards the development of green corrosion inhibitors have intensified recently. The objectiveof the current work was to develop novel green and sustainable corrosion inhibitors derived from 4-aminoantipyrine to effectively prevent corrosion of mild steel in corrosive environments. Gravimetricmethods were used to investigate corrosion inhibition of 4-((furan-2-ylmethylene)amino)antipyrine (FAP)and 4-((pyridin-2-ylmethylene)amino)antipyrine (PAP) for mild steel in 1 M HCl. FAP and PAP were subjectedto quantum chemical calculations using density functional theory (DFT). DFT was used to determinethe mechanism of mild steel corrosion inhibition using inhibitors tested in HCl. Results demonstratedthat these tested inhibitors could effectively inhibit mild steel corrosion in 1.0 M HCl. At 0.0005 M, theseinhibitors’ efficiencies for FAP and PAP were 93.3% and 96.5%, respectively. The Langmuir adsorptionisotherm was obeyed by these inhibitors on the mild steel surface. Values of adsorption free energies,, revealed that FAP followed chemical and physical adsorptions.

Abstract

Due to continuous promotion of green alternatives to toxic petrochemicals by government policies,research efforts towards the development of green corrosion inhibitors have intensified recently. The objectiveof the current work was to develop novel green and sustainable corrosion inhibitors derived from 4-aminoantipyrine to effectively prevent corrosion of mild steel in corrosive environments. Gravimetricmethods were used to investigate corrosion inhibition of 4-((furan-2-ylmethylene)amino)antipyrine (FAP)and 4-((pyridin-2-ylmethylene)amino)antipyrine (PAP) for mild steel in 1 M HCl. FAP and PAP were subjectedto quantum chemical calculations using density functional theory (DFT). DFT was used to determinethe mechanism of mild steel corrosion inhibition using inhibitors tested in HCl. Results demonstratedthat these tested inhibitors could effectively inhibit mild steel corrosion in 1.0 M HCl. At 0.0005 M, theseinhibitors’ efficiencies for FAP and PAP were 93.3% and 96.5%, respectively. The Langmuir adsorptionisotherm was obeyed by these inhibitors on the mild steel surface. Values of adsorption free energies,, revealed that FAP followed chemical and physical adsorptions.

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