scholarly journals Insight into Anticorrosion Mechanism of Ampicillin on Mild Steel in Acidic Environment: A Combined Experimental and Theoretical Approach

2021 ◽  
Vol 2021 ◽  
pp. 1-12
Author(s):  
Tuan Dinh ◽  
Nguyen Minh Thong ◽  
Dinh Quy Huong ◽  
Trinh Le Huyen ◽  
Tran Duc Manh ◽  
...  
Keyword(s):  
Mild Steel ◽  
Molecular Orbital ◽  
Corrosion Inhibition ◽  
Inhibition Efficiency ◽  
Energy Gap ◽  
Electrochemical Impedance ◽  
Carbon Steels ◽  
Orbital Energy ◽  
Acidic Environment ◽  
Molecular Orbital Energy

The corrosion inhibition of mild carbon steels in an acidic environment by using ampicillin (AMP) has been evaluated based on experimental and quantum chemistry techniques. The experimental results indicate that the inhibition efficiency goes up at higher AMP concentration. The highest inhibition efficiency reaches 84.9% for polarization measurement and 90.1% for electrochemical impedance spectroscopy with the inhibitor of concentration 100 ppm at 298 K. The surface characteristics (SEM) also reconfirm the steel corrosion inhibition ability of AMP. Some important chemical factors such as EHOMO (highest occupied molecular orbital energy), ELUMO (lowest unoccupied molecular orbital energy), ΔEL−H (energy gap), and Fukui functions were calculated based on the optimized configuration of AMP at the theoretical level of B3LYP/6-31+G(d,p). Moreover, Monte Carlo and molecular dynamics simulations were used to analyze the absorption behavior of inhibitor on the surface of Fe(110), which supplies the mechanism of inhibition corrosion processes. The obtained results showed that AMP is considered to be a potential corrosion inhibitor for mild steel in 1M HCl medium. Moreover, the protonated state of AMP plays an important role in the protection of Fe surface against the corrosive process.

The experimental and quantum chemical investigation for two isomeric compounds as aminopyrazine and 2-amino-pyrimidine against mild steel corrosion

2016 ◽  
Vol 63 (5) ◽  
pp. 369-376 ◽  
Author(s):  
Basak Dogru Mert ◽  
Mehmet Erman Mert ◽  
Gülfeza Kardas ◽  
Birgül Yazici
Keyword(s):  
Mild Steel ◽  
Molecular Orbital ◽  
Density Functional ◽  
Inhibition Efficiency ◽  
Electrochemical Impedance ◽  
Molecular Geometry ◽  
Orbital Energy ◽  
Content Type ◽  
Inhibition Effect ◽  
Amino Pyrimidine

Purpose The purpose of this paper is to investigate the adsorption and corrosion inhibition of two isomeric compounds (C4H5N3) as aminopyrazine (AP) and 2-amino-pyrimidine (2AP) on mild steel (MS) in 0.5 M HCl. The study was a trial to combine experimental and modelling studies and research effect of molecular geometry on inhibition effect of inhibitor molecules. Design/methodology/approach The thermodynamic, kinetic and quantum parameters were determined. The electrochemical impedance spectroscopy and anodic polarisation measurements were obtained. The scanning electron microscope was used for monitoring electrode surface. The highest occupied molecular orbital, energy of the lowest unoccupied molecular orbital, Mulliken and natural bonding orbital charges on the backbone atoms, absolute electronegativity, absolute hardness were calculated by density functional theory (DFT)/B3LYP/6-311G (++ d,p). Findings Results showed that AP and 2AP suppressed the corrosion rate of MS. The corrosion current values were 0.530, 0.050 and 0.016 mA cm-2 in HCl, AP and 2AP containing HCl solutions, respectively. It was illustrated with the blocked fraction of the MS surface by adsorption of inhibitors which obeyed the Langmuir isotherm. The inhibition efficiency follows the order: 2AP > AP which is in agreement with experimental and quantum results. Originality/value This paper provides lay a bridge on the molecular geometry and inhibition efficiency by electrochemical tests and modelling study. The inhibition effect of AP and 2AP has not been compared with each other, neither experimentally nor theoretically. This study put forward possible application of 2AP as corrosion inhibitor especially for closed-circuit systems.

scholarly journals Theoretical Evaluation of the Corrosion Inhibition Performance of an Organic Heterocyclic Compound

2021 ◽  
Vol 18 (6) ◽  
Author(s):  
Zineb TRIBAK ◽  
Mohammed Khalid SKALLI ◽  
Omar SENHAJI
Keyword(s):  
Molecular Orbital ◽  
Corrosion Inhibition ◽  
Density Functional ◽  
Energy Gap ◽  
Chemical Properties ◽  
Orbital Energy ◽  
Total Hardness ◽  
Theoretical Evaluation ◽  
Molecular Orbital Energy ◽  
Inhibition Performance

The corrosion inhibition performance of a corrosion inhibitor on mild steel in phosphoric acid, namely 5-chloro-1-(2-(dimethylamino) ethyl) indoline-2,3-dione (TZCDI), was theoretically evaluated using density functional theory (DFT) at the B3LYP/6-31G+(d,p) level for all atoms by Gaussian 09W program. The quantum chemical properties, such as highest occupied molecular orbital energy (EHOMO), lowest unoccupied molecular orbital energy (ELUMO) energy gap (∆Egap), dipole moment (μ), total hardness (η), and electronegativity (χ), were studied, and these descriptors were discussed in connection to the experimental inhibitory efficiency. The local reactivity was analyzed through the Fukui function in order to compare the possible sites for nucleophilic and electrophilic attacks. Accordingly, all data obtained using various theoretical calculation techniques were consistent with experiments.

scholarly journals Spilanthes acmella Leaves Extract for Corrosion Inhibition in Acid Medium

Coatings ◽  
2021 ◽  
Vol 11 (1) ◽  
pp. 106
Author(s):  
Akbar Ali Samsath Begum ◽  
Raja Mohamed Abdul Vahith ◽  
Vijay Kotra ◽  
Mohammed Rafi Shaik ◽  
Abdelatty Abdelgawad ◽  
...  
Keyword(s):  
Mild Steel ◽  
Corrosion Inhibition ◽  
Active Sites ◽  
Inhibition Efficiency ◽  
Electrochemical Impedance ◽  
Film Formation ◽  
Protective Film ◽  
Surface Protection ◽  
Tafel Polarization ◽  
Spilanthes Acmella

In the present study, the corrosion inhibition effect of Spilanthes acmella aqueous leaves extract (SA-LE) on mild steel was investigated in 1.0 M HCl solution at different temperature using weight loss, Tafel polarization, linear polarization resistance (LPR), and electrochemical impedance (EIS) measurements. Adsorption of inhibitor on the surface of the mild steel obeyed both Langmuir and Temkin adsorption isotherms. The thermodynamic and kinetic parameters were also calculated to determine the mechanism of corrosion inhibition. The inhibition efficiency was found to increase with an increase in the inhibitor concentration i.e., Spilanthes acmella aqueous leaves extract, however, the inhibition efficiency decreased with an increase in the temperature. The phytochemical constituents with functional groups including electronegative hetero atoms such as N, O, and S in the extract adsorbed on the metal surface are found responsible for the effective performance of the inhibitor, which was confirmed by Fourier-transform infrared spectroscopy (FT-IR) and ultraviolet–visible spectroscopic (UV-Vis) studies. Protective film formation against corrosion was confirmed by scanning electron microscopy (SEM), atomic force microscopy (AFM), and contact angle studies. The result shows that the leaves extract acts as corrosion inhibitor and is able to promote surface protection by blocking active sites on the metal.

scholarly journals Corrosion Inhibition of Mild Steel in Acidic Media by N-[(3,4-Dimethoxyphenyl)Methyleneamino]-4-Hydroxy-Benzamide

2020 ◽  
Vol 7 (1) ◽  
Author(s):  
Kashmitha Muthamma ◽  
Preethi Kumari ◽  
M. Lavanya ◽  
Suma A. Rao
Keyword(s):  
Dft Calculations ◽  
Mild Steel ◽  
Corrosion Inhibition ◽  
Density Functional ◽  
Surface Characterization ◽  
Inhibition Efficiency ◽  
Electrochemical Impedance ◽  
Corrosion Behaviour ◽  
Low Carbon ◽  
Acid Media

Abstract Mild steel (a low carbon steel) is an affordable engineering material used for many purposes in various environments including mild acidic environment with some precautions. The corrosion behaviour of mild steel (MS) in 0.5 M H2SO4 and 0.5 M HCl, in the temperature range (303–323 K) without and with the inhibitor N-[(3,4-dimethoxyphenyl) methyleneamino]-4-hydroxy-benzamide (DMHB), was investigated using Potentiodynamic polarization and Electrochemical impedance spectroscopy (EIS) techniques supplementing with surface characterization study using scanning electron microscope (SEM) and atomic force spectroscopy (AFM). Experimental observations were found to be in agreement with Density functional theory (DFT) calculations. The inhibition efficiency increases with increase in DMHB concentration and showed maximum inhibition efficiency of 86% in 0.5 M H2SO4 and 81% in 0.5 M HCl, respectively, at concentration of 3 × 10─3 M at 303 K. The inhibition efficiency of DMHB obtained relatively at its lower concentration (3 × 10─3 M) compared to other reported related compounds confirms its potential towards corrosion inhibition. The variation in the kinetic and thermodynamic parameters indicated physisorption of DMHB on MS and its mixed type inhibitive action followed Langmuir’s isotherm model. DFT calculations go along with the experimental results, signifying the potential corrosion inhibition behaviour of DMHB for MS in both the acid media.

scholarly journals Dielectric, Electrical Conductivity Behavior and Molecular Modeling of Some Pyrimidine and Purine Compounds

2021 ◽  
Vol 5 (1) ◽  
Keyword(s):  
Electrical Conductivity ◽  
Molecular Modeling ◽  
Molecular Orbital ◽  
Temperature Region ◽  
Chemical Potential ◽  
Energy Gap ◽  
Relaxation Times ◽  
Biologically Active ◽  
Orbital Energy ◽  
Molecular Orbital Energy

The dielectric and electrical conductivity measurements for biologically active nucleic acid compounds reveal semiconducting properties and small relaxation times. On the basis of electronic transition within molecules, two pathways for the conduction of electricity may be expected. The first conducting process occurring in the lower temperature region is attributed to n→π* transitions which require less energy to be performed. In the upper temperature region, conduction could be attributed to π→π* transitions which need more energy to participate in electronic conduction. The observed increment of conduction in the upper temperature region may be attributed to interactions between n→π* and π→π* transitions. Quantum chemical parameters such as the highest occupied molecular orbital energy (EHOMO) and the lowest unoccupied molecular orbital energy (ELUMO) were given using molecular modeling. Energy gap (ΔE) and parameters which give information about the reactive chemical behavior of compounds such as electronegativity (χ), chemical potential (µ), global hardness (η), softness (σ) and electrophilicity index (ω) were calculated.

scholarly journals Corrosion Inhibition of Mild Steel in Acid Solution by 3,4,5-Trimethoxyphenyl-2-imidazolines

2011 ◽  
Vol 8 (2) ◽  
pp. 671-679 ◽  
Author(s):  
D. Nalini ◽  
R. Rajalakshmi ◽  
S. Subhashini
Keyword(s):  
Mild Steel ◽  
Corrosion Inhibition ◽  
Mixed Mode ◽  
Anodic Polarization ◽  
Inhibition Efficiency ◽  
Electrochemical Impedance ◽  
Langmuir Adsorption Isotherm ◽  
Sem Images ◽  
Acid Media ◽  
Langmuir Adsorption

A heterocyclic imidazoline, 3,4,5-trimethoxyphenyl-2-imidazolines (TMP2I) was tested for its corrosion inhibition in 0.5 M H2SO4and 1 M HCl using weight loss, Tafel polarisation and electrochemical impedance techniques. The results show that the inhibition efficiency increases with the increase in concentration of TMP2I and the higher efficiency of about 98% is obtained in both the acid media at 20 ppm. The adsorption of TMP2I obeys Langmuir adsorption isotherm and occurs spontaneously. Cathodic and anodic polarization curves of mild steel in the presence of different concentrations of TMP2I at 300C reveal that it is a mixed type of inhibitor. Electrochemical impedance studies reveal that the system follows mixed mode of inhibition. The surface morphology of the mild steel specimens was evaluated using SEM images

The Synergistic Impact of the Aqueous Valerian Extract and Zinc Ions for the Corrosion Protection of Mild Steel in Acidic Environment

2019 ◽  
Vol 233 (12) ◽  
pp. 1713-1739
Author(s):  
Emad E. El-Katori ◽  
A.S. Fouda ◽  
Rahma R. Mohamed
Keyword(s):  
Mild Steel ◽  
Corrosion Inhibition ◽  
Electrochemical Impedance ◽  
Attenuated Total Reflection ◽  
Inhibition Mechanism ◽  
Acidic Environment ◽  
Complete Study ◽  
Weight Loss Method ◽  
Loss Method ◽  
Inhibition Performance

AbstractHerein, the corrosion inhibition performance of mild steel (MS) in an acidic environment (1.0 M HCl) by the valerian extract has been studied via weight loss method (WL), potentiodynamic polarization (PP), electrochemical impedance spectroscopy (EIS) and electrochemical frequency modulation (EFM) techniques. The results illustrated that the inhibition efficiency, raised by the rise of the extract concentrations. The inhibitory mechanism depended on the creation of a stable plant extract-complex on the mild steel surface. Polarization studies confirmed that the extract behaved as a mixed type inhibitor. The corrosion inhibition was supposed to exist via adsorption of the main components of the valerian extract. Attenuated total reflection-infrared spectroscopy (ATR-IR), scanning electron microscopy (SEM) and atomic force microscopy (AFM) were applied to investigate the change in the surface morphology and confirmed the corrosion inhibition mechanism. The complete study confirmed that the efficiency of the valerian extract as a safe, eco-friendly and exchange corrosion inhibition for mild steel in an acidic environment.

Mild steel protection with tannic and polyaspartic acid in cooling systems

2019 ◽  
Vol 66 (5) ◽  
pp. 583-594
Author(s):  
Esma Sezer ◽  
İpek Öztürk
Keyword(s):  
Mild Steel ◽  
Corrosion Inhibition ◽  
Inhibition Efficiency ◽  
Electrochemical Impedance ◽  
Electrochemical Techniques ◽  
Inhibition Mechanism ◽  
Polyaspartic Acid ◽  
Cooling Systems ◽  
Environmental Aspect ◽  
Content Type

Purpose Tannic acid (TA) is one of the green corrosion inhibitors for mild steel; its anti-corrosive performance in alkaline water on mild steel when it is used together with polyaspartic acid (PASA) still has not been investigated. The purpose of this study is to develop an effective, biodegradable and environment-friendly novel corrosion inhibitor based on TA and PASA as an alternative to the conventional inorganic inhibitors for mild steel in decarbonised water, which is common in cooling systems. Design/methodology/approach Corrosion inhibition mechanism is investigated by electrochemical techniques such as polarisation measurements and electrochemical impedance spectroscopy, and results were evaluated to determine the optimum inhibitor concentration for industrial applications. Additionally, practice-like conditions are carried out in pilot plant studies to simulate the conditions in cooling systems. Thus, the efficiencies of the inhibitors are evaluated through both weight loss and linear polarisation resistance measurements. Moreover, the corrosion product is characterised by scanning electron microscopy with energy dispersive X-ray spectroscopy (SEM-EDX) and Fourier-transform infrared spectroscopy (FTIR) analysis. Findings TA shows high inhibition efficiency especially towards pitting corrosion for mild steel in decarbonised water. PASA addition in the cooling systems improves the inhibition efficiency of TA, and at lower concentrations of TA + PASA, it is possible to obtained better inhibition efficiency than TA alone at higher inhibitor amounts, which is essential in economic and environmental aspect. Originality/value A blended inhibitor program including TA and PASA with suggested concentrations in this work can be used as an environmental friendly treatment concept for the mild steel corrosion inhibition at cooling systems.

Revealing the Inhibition Efficiencies of Artesunate and Rutin for Corrosion of Steel: A Theoretical Study

2018 ◽  
Vol 762 ◽  
pp. 325-329 ◽  
Author(s):  
Gökhan Gece
Keyword(s):  
Molecular Orbital ◽  
Density Functional ◽  
Energy Gap ◽  
Theoretical Calculations ◽  
Aqueous Media ◽  
Basis Set ◽  
Orbital Energy ◽  
Molecular Orbital Energy ◽  
Experimental Findings ◽  
Corrosion Of Steel

Corrosion inhibition characteristics of artesunate and rutin on carbon steel in water has been studied using density functional theory (DFT). Quantum chemical parameters such as highest occupied molecular orbital energy (EHOMO), lowest unoccupied molecular orbital energy (ELUMO), energy gap (ΔE), and global reactivity properties have been calculated at the B3LYP/6-311G(d,p) basis set. The results of theoretical calculations confirm the experimental findings on the superiority of rutin to protect the corrosion of steel in aqueous media compared to artesunate.

scholarly journals Gravimetrical, theoretical, and surface morphological investigations of corrosion inhibition effect of 4-(benzoimidazole-2-yl) pyridine on mild steel in hydrochloric acid

2020 ◽  
Vol 64 (4) ◽  
pp. 122-130
Author(s):  
A.M. Resen ◽  
M. Hanoon ◽  
R.D. Salim ◽  
A.A. Al-Amiery ◽  
L.M. Shaker ◽  
...  
Keyword(s):  
Hydrochloric Acid ◽  
Mild Steel ◽  
Corrosion Inhibitor ◽  
Molecular Orbital ◽  
Corrosion Inhibition ◽  
Density Functional ◽  
Energy Gap ◽  
Mechanism Of Inhibition ◽  
Acid Environment ◽  
And Behavior

Abstract The corrosion inhibition efficiency of the novel pyridine namely, 4-(Benzoimidazole-2-yl)pyridine has been studied for mild steel in a 1 M hydrochloric acid environment by utilizing gravimetrical techniques. The synthesized inhibitor exhibits a significant inhibitive efficiency of 93.8% at 0.005 M. The adsorption isotherm of the investigated inhibitor on mild steel surface obeys the Langmuir isotherm. Surface morphology investigated by utilizing scanning electron microscopy (SEM) demonstrates a smooth metal surface with the addition of 4-(Benzoimidazole-2-yl)pyridine in a hydrochloric acid environment. Quantum chemical calculations using density functional theory (DFT) have been used to investigate the molecular structure and behavior of 4-(Benzoimidazole-2-yl) pyridine as a corrosion inhibitor. Different parameters have been calculated using DFT, such as energies of highest occupied molecular orbital and lowest occupied molecular orbital (EHOMO and ELUMO), energy gap (∆E), and dipole moment (μ). These parameters were important to elucidate the behavior of the investigated molecule as a corrosion inhibitor in acidic solution and also suggest the mechanism of inhibition.

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