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Experiments were conducted with carbon steel to investigate the corrosion protection performance of five commercial chemicals as inhibitors in oil field effluent and aquifer waters. The effect of different inhibitor concentrations and flow velocity was determined using the disc electrode (RDE) method. The corrosion rate of carbon steel under stagnant and flow conditions was determined by the linear polarization resistance (LPR) method at a scan rate of 0.1mV/s versus a saturated calomel electrode (SCE). All experiments were conducted at 82^○C. Results indicated that a blend of ethoxylated amine inhibitor for the effluent water, alkylpyridinium‐oxyalkylated‐alkylphenol amine salts inhibitor was found to be the best for both the effluent and aquifer waters.

The purpose of this paper is to investigate three Arylfuranylnicotinamidine derivatives against corrosion of carbon steel (C-steel) in 1.0 M HCl by chemical and electrochemical means. The inhibition efficiency (%IE) increases with increasing the dose of inhibitors. The tested compounds exhibited improved performance at elevated temperature, with %IE reaching 93 percent at 21 µM. Tafel polarization method revealed that the tested compounds act as mixed-type inhibitors. The inhibition action was rationalized due to chemical adsorption of inhibition molecules on C-steel surface following Temkin’s isotherm. Surface examination was carried out by AFM and FTIR techniques. Further, theoretical chemical approaches were used to corroborate the experimental findings.

Experimental and computational methods were applied to investigate the efficiency of these new compounds. These studies are complemented with spectral studies and surface morphological scan by AFM. The theoretical results indicate good correlation with experimental findings.

The tested derivatives are promising corrosion inhibitors for C-steel in the acid environment. The molecular scaffold of this class of compounds can be used to design new highly efficient inhibitors by screening its activity by modeling studies.

The studied compounds are safe inhibitors and greatly adsorbed on Fe surface. The action of compounds is enhanced with temperature, which means these compounds can be used in higher temperature systems. The new compounds are effective at very low concentration.

The aim of this study is to evaluate the corrosion inhibitory properties of three piperazine derivatives – Ethyl 5-(piperazine-1-yl) benzofuran-2-carboxylate (EPBC), 5-[4–(1-tert-butoxyethenyl) piperazin-1-yl]-1-benzofuran-2-carboxamide (BBPC) and Tert-butyl-4–(2-(ethoxycarbonyl)benzofuran-5-yl)-piperazine-1-carboxylate (TBPC) – on Al surfaces in the presence of hydrochloric acid (HCl). The research uses density functional theory (DFT) and molecular dynamics simulations to explore the effectiveness of these derivatives as corrosion inhibitors and to understand their adsorption behavior at the molecular level.

This study uses a computational approach using DFT at various levels (B3LYP/6–31+G(d,p), B3LYP/6–311+G(d,p), WB97XD/DGDZVP) to calculate essential quantum chemical parameters such as energy gap (ΔE), ionization energy (I), absolute electronegativity (χ), electron affinity (E), dipole moment (µ), absolute softness (s), fraction of electron transferred (ΔN) and absolute hardness (η). The Fukui function and local softness indices are used to assess the sites for electrophilic and nucleophilic attacks on the inhibitors. Molecular dynamics simulations are performed to analyze the adsorption behavior of these derivatives on the Al (110) surface using the adsorption locator method. Theoretical methods like DFT provide quantum chemical parameters, explaining inhibitor reactivity, whereas molecular dynamics simulate adsorption behavior on Al (110), both supporting and correlating with experimental inhibition efficiency trends.

This study demonstrates that all three piperazine derivatives exhibit strong adsorption on the Al surface, with high adsorption energies, good solubility and low toxicity, making them effective corrosion inhibitors in acidic environments. Among the three, TBPC showed superior inhibitory performance, particularly in the presence of HCl, due to its optimal electronic properties and stable adsorption on the Al (1 1 0) surface.

This research contributes to the field by combining DFT calculations and molecular dynamic simulations to evaluate the corrosion inhibition potential of piperazine derivatives comprehensively. This work advances the understanding of the adsorption mechanisms of organic inhibitors on metal surfaces and offers a detailed quantum chemical and adsorption behavior analysis.

Use of chemical inhibitors is a technique of rapidly increasing importance in the never‐ending fight against corrosion of refinery equipment. The method itself is not new. But with growing complexity of the corrosion problem, development of inhibiting techniques has made rapid strides, especially during the post‐war years. Today, the plant operator has at his disposal a large number of chemical corrosion preventives which may result in substantial reduction in maintenance costs, provided they are properly applied.

This paper aims to study the inhibition effect of 2-pyridinealdazine on the corrosion of mild steel in an acidic medium. The inhibition effect was studied using weight loss, electrochemical impedance spectroscopy, and Tafel polarization measurements.

Weight loss measurements, potentiodynamic tests, electrochemical impedance spectroscopy, X-ray diffraction and spectral and conformational isomers analysis of A (E-PAA) and B (Z-PAA) were performed were investigated.

2-pyridinealdazine (PAA) acts as a good inhibitor for the corrosion of steel in 2.0 M H₃PO₄. The inhibition efficiency increases with an increase in inhibitor concentration but decreases with an increase in temperature.

This paper is intended to be added to the family of azines which are highly efficient inhibitors and can be used in the area of corrosion prevention and control.

The aim of this paper was to investigate the corrosion inhibition potential of two synthesized benzothiazines, namely, 3,4-dihydro-2-methoxycarbonylmethyl-3-oxo-2H-1,4-benzothiazine (1) and ethyl 3-oxo-3,4-dihydro-2H-1,4-benzothiazine-2-carboxylate (2) on mild steel corrosion in 1M H₂SO₄.

Corrosion inhibition efficiency (IE%) was studied by weight loss measurements, potentiodyanmic polarization method, alternating current (AC) impedance spectroscopy, fourier transform infrared (FT-IR) spectroscopy and scanning electron microscopy. Quantum chemical approach was used to complement the experimental results.

The results obtained show that the IE% increased with inhibitor concentration and follow the order 2 > 1, obeying Langmuir adsorption isotherm. The calculated quantum chemical indices were consistent with experimental results.

This paper provides information on the inhibitive properties of new set of benzothiazines on mild steel corrosion in 1M H₂SO₄.

This study aims is to evaluate the environmentally friendly turmeric as a corrosion inhibitor for mild steel in a simulated seawater corrosion medium such as a 3.5% NaCl solution. To accomplish this, different proportions of turmeric (0.3, 0.6, 0.9 and 1.5%) were added to solvent-free epoxy-acrylate resin-based coating formulations. Then, all the formulations were sonicated and coated as thin films on different substrates; these coated films were then polymerized under a dose of 10 kGy of electron beam (EB) radiation.

Various properties of all cured coating films such as Fourier transform infrared spectroscopy, water contact angle, thermogravimetric analysis and scanning electron microscopy were studied, in addition to their physical, chemical and mechanical properties. Turmeric was then evaluated in these formulations as an anticorrosion agent for mild steel in 3.5% NaCl. The different corrosion-resistant properties of all EB-cured coating films were evaluated by open circuit potential measurements, rust degree, blistering, adhesion loss at X-cut and weight loss measurements.

The results showed that most of the formulations are homogeneous, especially at low concentrations of turmeric, and their films have high-performance properties.

It was also found that the formulation containing 0.6% of turmeric per 100 g of coating was considered the best formulation as it gave the highest protection to the mild steel plates with no negative effects on the chemical and physical properties of their films.

This work describes test results that were obtained using a newly-developed type of organic inhibitor: V-active VCIs. The findings demonstrate that is possible to eliminate or reduce the oxidizing action of water, thereby extending the allowable time before painting after hydrojetting, and that the new corrosion inhibitor technology does not interfere with the final quality of paint adhesion.

Metallic specimens were treated/washed by hydrojet (35000 Psi). It was employed as a 2 per cent V-active VCI SPH 1,712 water solution by dilution of the inhibitor in industrial water. Metal sample plates were examined after blasting and after subsequent drying, and were submitted to the paint adhesion tests, to evaluate the duration of temporary protection, oxidation prevention and influence on the adherence of paint (pull off).

Using the V-active VCI proposed technology, it was possible to minimize or eliminate the oxidizing action of the water when the metal is exposed to the saline moisture in a closed environment, extending the acceptable time before painting without interference in the final quality of painting.

The proposed technology allows to the area of prepared (wet blasted) steel surface to be increased during cleaning and preparation, thereby reducing labor and product costs, and reduces water consumption during the preparation process. Practical applications in the shipbuilding, ship maintenance and oil and gas production industries, include the preservation of internal tubes and pipes, protection during hydrostatic test processes and cleaning with water and corrosion prevention in diesel tanks contaminated with water.

The intent of this paper is to present the obtained results for a new formulation of organic chemical inhibitors that use water medium as the application method. In addition to this property, this group of organic inhibitors maintains the property of volatile inhibitors. Thus, these compounds are generically known as V-active VCI.

This paper aims to describe the results of lab testing of a newly developed organic inhibitor V-active VCIs. The findings demonstrate that it is possible to eliminate or reduce the oxidizing action of water, thereby extending the allowable time before painting after hydrojetting, and that the new corrosion inhibitor technology does not interfere with the final quality of paint adhesion.

Metallic specimens were treated/washed in standard lab condition. A 2 per cent V-active VCI SPH1712 water solution was prepared by diluting the inhibitor in industrial water. Metal sample plates were examined after blasting and after subsequent drying, and were submitted to the paint adhesion tests, cathodic disbondment, total soluble salts, time for formation of flash rust and cyclic corrosion test type III (20 cycles), to evaluate the duration of temporary protection and oxidation prevention and influence on paint adherence.

Using the V-active VCI proposed technology, it was possible to minimize or eliminate the oxidizing action of the water when the metal is exposed to saline moisture in a closed environment, extending the acceptable time before painting without interfering with the final quality of painting.

The proposed technology allows an increase in the prepared (wet blasted) steel surface during cleaning and preparation, thereby reducing labor and product costs, and reduces water consumption during the preparation process. Practical applications in the shipbuilding, ship maintenance and oil and gas production industries include the preservation of internal tubes and pipes, protection during hydrostatic test processes and cleaning with water and corrosion prevention in diesel tanks contaminated with water.

The intent of this paper is to present the obtained results for a new formulation of organic chemical inhibitors that use water as the application medium. In addition to this property, this group of organic inhibitors maintains the properties of volatile inhibitors. Thus, these compounds are generically known as V-active VCIs.

The purpose of this study is to inspect the corrosion inhibition of API N80 steel pipelines in uninhibited solution and inhibited with a synthesized surfactant compound [N-(3-(dimethyl octyl ammonio) propyl) palmitamide bromide] (DMDPP), which is prepared through a simple and applicable method.

Weight loss was inspected at five different temperatures of 25°C, 30°C, 40°C, 50°C and 60°C Potentiodynamic polarization, electrochemical impedance spectroscopy (EIS) and electrochemical frequency modulation were used at room temperature. Density functional theory was used to study the relation between the molecular structure and inhibition theoretically.

Adsorption of the prepared DMDPP fits the Langmuir isotherm model. The inhibition efficiency of the prepared DMDPP amphipathic inhibitor is directly proportional to temperature increase. Polarization results reveal that the investigated DMDPP amphipathic compound behaves as a mixed-type inhibitor. EIS spectra produced one individual capacitive loop.

The originality is the preparation of cationic surfactants through a simple method, which can be used as corrosion inhibitors in oil production. The synthesized inhibitors were prepared from low-price materials. The work studied the behavior of the synthesized surfactants in inhibiting the corrosion of the steel in an acidic medium. Electrochemical and theoretical studies were presented, besides gravimetric and surface examination.