Materials Science › Materials Chemistry

Corrosion Behavior and Inhibition

Description

This cluster of papers focuses on the development and application of corrosion inhibitors, including organic compounds and plant extracts, for the protection of metals from corrosion in various aggressive environments. The research encompasses electrochemical impedance spectroscopy, molecular dynamics simulations, and the investigation of self-healing mechanisms in protective coatings. Additionally, it explores the impact of sulfate-reducing bacteria on metal corrosion.

Keywords

Corrosion Inhibitors; Metal Corrosion; Electrochemical Impedance Spectroscopy; Organic Coatings; Molecular Dynamics Simulation; Green Inhibitors; Adsorption Properties; Quantum Chemical Studies; Self-Healing Coatings; Sulfate-Reducing Bacteria

A model based on the movement of point defects in an electrostatic field is proposed to interpret the growth behavior of a passive film on a metal surface. This model … A model based on the movement of point defects in an electrostatic field is proposed to interpret the growth behavior of a passive film on a metal surface. This model results in a logarithmic growth law. The theoretical equations derived from the model readily account for experimental data for the growth of a passive film on iron. It is found that the field strength of the film is . The dependence of film/solution interface potential difference on the applied potential (α) was found to be 0.743, and is independent of the identity of the anion in solution. However, the dependence of the potential difference across the film/solution interface on the solutionpH (β) is strongly dependent on the identity of the solution anion.
Definition and Importance. Electrochemical Mechanisms. Corrosion Tendency and Electrode Potentials. Polarization and Corrosion Rates. Passivity. Iron and Steel. Effect of Stress. Atmospheric Corrosion of Iron and Other Metals. Corrosion of … Definition and Importance. Electrochemical Mechanisms. Corrosion Tendency and Electrode Potentials. Polarization and Corrosion Rates. Passivity. Iron and Steel. Effect of Stress. Atmospheric Corrosion of Iron and Other Metals. Corrosion of Iron and Other Metals in Soil. Oxidation and Tarnish. Stray--Current Corrosion. Cathodic Protection. Metallic Coatings. Inorganic Coatings. Organic Coatings. Inhibitors and Passivators. Treatment of Water and Steam Systems. Alloying for Corrosion Resistance. Stainless Steels. Copper and Copper Alloys. Aluminum and Magnesium. Lead. Nickel and Nickel Alloys. Cobalt and Cobalt Alloys. Titanium, Zirconium, and Tantalum. Silicon--Iron and Silicon--Nickel Alloys. Problems. Appendix. Index.
Introduction to Surface Reactions: Electrochemical Basis of Corrosion, D. Landolt Introduction to Surface Reactions: Adsorption from Gas Phase, J. Oudar Surface Effects on Hydrogen Entry into Metals, E. Protopopoff and … Introduction to Surface Reactions: Electrochemical Basis of Corrosion, D. Landolt Introduction to Surface Reactions: Adsorption from Gas Phase, J. Oudar Surface Effects on Hydrogen Entry into Metals, E. Protopopoff and P. Marcus Anodic Dissolution, M. Keddam Thin Oxide Film Formation on Metals, F.P. Fehlner and M.J. Graham Growth and Stability of Passive Films, B. MacDougall and M.J. Graham Passivity of Austenitic Stainless Steels, C.R. Clayton and I. Olefjord Mechanisms of Pitting Corrosion, H.-H. Strehblow Sulfur-Assisted Corrosion Mechanisms and the Role of Alloyed Elements, P. Marcus Further Insights on the Pitting Corrosion of Stainless Steels, B. Baroux Crevice Corrosion of Metallic Materials, P. Combrade Stress-Corrosion Cracking Mechanisms, R.C. Newman Corrosion Fatigue Mechanisms in Metallic Materials, T. Magnin Corrosion Prevention by Adsorbed Organic Monolayers and Ultrathin Plasma Polymer Films, M. Rohwerder, G. Grundmeier, and M. Stratmann Atmospheric Corrosion, C. Leygraf Microbially Influenced Corrosion, D. Thierry and W. Sand Corrosion in Nuclear Systems: Environmentally Assisted Cracking in LightWater Reactors, F.P. Ford and P.L. Andresen Corrosion of Microelectronic and Magnetic Data-Storage Devices, G.S. Frankel and J.W. Braithwaite Organic Coatings, J.H.W. de Wit, D.H. der Weijde, and G. Ferrari Index
To understand the role of structure on the position of the octahedral redox couple in compounds having the same polyanions, four iron phosphates: , and were investigated. They vary in … To understand the role of structure on the position of the octahedral redox couple in compounds having the same polyanions, four iron phosphates: , and were investigated. They vary in structure as well as in the manner in which the octahedral iron atoms are linked to each other. The redox couple in the above compounds lies at 2.8, 2.9, 3.1, and 3.5 eV, respectively, below the Fermi level of lithium. The reason for the difference in the position of the redox couples is related to changes in the P‒O bond lengths as well as to changes in the crystalline electric field at the iron sites.
This review summarizes the corrosion inhibition of steel materials in acidic media. Numerous corrosion inhibitors for steels in acidic solutions are presented. The emphasis is on HCl solutions, lower-grade steels, … This review summarizes the corrosion inhibition of steel materials in acidic media. Numerous corrosion inhibitors for steels in acidic solutions are presented. The emphasis is on HCl solutions, lower-grade steels, and elevated temperatures. This review is also devoted to corrosion inhibitor formulation design – mixtures of corrosion inhibitors with (mainly) surfactants, solvents, and intensifiers to improve the effectiveness of individual compounds at elevated temperatures. The information presented in this review is useful for diverse industrial fields, primarily for the well acidizing procedure, and secondly for other applications where corrosion inhibitors for steel materials are needed.
Corrosion inhibition efficiencies of heterocyclic, unsaturated (aromatic and nonaromatic) compounds (pyrimidines, benzothiazole derivatives, amino acids containing an aromatic part, pyridines, and quinolines) were correlated with quantum chemical indices of the … Corrosion inhibition efficiencies of heterocyclic, unsaturated (aromatic and nonaromatic) compounds (pyrimidines, benzothiazole derivatives, amino acids containing an aromatic part, pyridines, and quinolines) were correlated with quantum chemical indices of the respective molecules. Inhibition efficiencies were determined in acidic solutions containing 0.001 M or 0.01 M of the inhibitor. Quantum chemical calculations were made by using the Hückel method. The difference (Ī”) between energy of the highest occupied and the lowest unoccupied molecular orbital was related to the inhibition efficiency (E) of the molecules. At values Ī” < 1.3 beta, efficiency increased with increasing values of Ī”. At values Ī” > 1.3 beta, efficiency (in 0.001 M concentration) tended to decrease with increasing values of Ī”. The optimal value of index Ī” may have been lower in solutions containing 0.01 M of the inhibitor. Results indicated that Ī” alone is insufficient to account for all variations in the experimental inhibition efficiency.
(1984). The Sulphate-Reducing Bacteria. British Corrosion Journal: Vol. 19, No. 2, pp. 55-55. (1984). The Sulphate-Reducing Bacteria. British Corrosion Journal: Vol. 19, No. 2, pp. 55-55.
About a century ago, researchers first recognized a connection between the activity of environmental microorganisms and cases of anaerobic iron corrosion. Since then, such microbially influenced corrosion (MIC) has gained … About a century ago, researchers first recognized a connection between the activity of environmental microorganisms and cases of anaerobic iron corrosion. Since then, such microbially influenced corrosion (MIC) has gained prominence and its technical and economic implications are now widely recognized. Under anoxic conditions (e.g., in oil and gas pipelines), sulfate-reducing bacteria (SRB) are commonly considered the main culprits of MIC. This perception largely stems from three recurrent observations. First, anoxic sulfate-rich environments (e.g., anoxic seawater) are particularly corrosive. Second, SRB and their characteristic corrosion product iron sulfide are ubiquitously associated with anaerobic corrosion damage, and third, no other physiological group produces comparably severe corrosion damage in laboratory-grown pure cultures. However, there remain many open questions as to the underlying mechanisms and their relative contributions to corrosion. On the one hand, SRB damage iron constructions indirectly through a corrosive chemical agent, hydrogen sulfide, formed by the organisms as a dissimilatory product from sulfate reduction with organic compounds or hydrogen ("chemical microbially influenced corrosion"; CMIC). On the other hand, certain SRB can also attack iron via withdrawal of electrons ("electrical microbially influenced corrosion"; EMIC), viz., directly by metabolic coupling. Corrosion of iron by SRB is typically associated with the formation of iron sulfides (FeS) which, paradoxically, may reduce corrosion in some cases while they increase it in others. This brief review traces the historical twists in the perception of SRB-induced corrosion, considering the presently most plausible explanations as well as possible early misconceptions in the understanding of severe corrosion in anoxic, sulfate-rich environments.
ADVERTISEMENT RETURN TO ISSUEPREVArticleNEXTNarrow molecular weight resins by a free-radical polymerization processMichael K. Georges, Richard P. N. Veregin, Peter M. Kazmaier, and Gordon K. HamerCite this: Macromolecules 1993, 26, 11, … ADVERTISEMENT RETURN TO ISSUEPREVArticleNEXTNarrow molecular weight resins by a free-radical polymerization processMichael K. Georges, Richard P. N. Veregin, Peter M. Kazmaier, and Gordon K. HamerCite this: Macromolecules 1993, 26, 11, 2987–2988Publication Date (Print):May 1, 1993Publication History Published online1 May 2002Published inissue 1 May 1993https://pubs.acs.org/doi/10.1021/ma00063a054https://doi.org/10.1021/ma00063a054research-articleACS PublicationsRequest reuse permissionsArticle Views8557Altmetric-Citations1878LEARN ABOUT THESE METRICSArticle Views are the COUNTER-compliant sum of full text article downloads since November 2008 (both PDF and HTML) across all institutions and individuals. These metrics are regularly updated to reflect usage leading up to the last few days.Citations are the number of other articles citing this article, calculated by Crossref and updated daily. Find more information about Crossref citation counts.The Altmetric Attention Score is a quantitative measure of the attention that a research article has received online. Clicking on the donut icon will load a page at altmetric.com with additional details about the score and the social media presence for the given article. Find more information on the Altmetric Attention Score and how the score is calculated. Share Add toView InAdd Full Text with ReferenceAdd Description ExportRISCitationCitation and abstractCitation and referencesMore Options Share onFacebookTwitterWechatLinked InRedditEmail Other access optionsGet e-Alertsclose Get e-Alerts
It is generally accepted that iron is the most important micronutrient used by bacteria. With members of the family Lactobacillae being the only exceptions so far ([3][1]), this metal is … It is generally accepted that iron is the most important micronutrient used by bacteria. With members of the family Lactobacillae being the only exceptions so far ([3][1]), this metal is essential for cellular metabolism, since it is needed as a cofactor for a large number of enzymes ([96][2]).
A review is presented of the point defect model (PDM) for the growth and breakdown of passive films on metal and alloy surfaces in contact with aqueous solutions. The model … A review is presented of the point defect model (PDM) for the growth and breakdown of passive films on metal and alloy surfaces in contact with aqueous solutions. The model provides a reasonable account of the steady‐state properties of cation‐conducting and anion‐conducting barrier layers on nickel and tungsten, respectively, in phosphate buffer solutions; of the impedance characteristics of passive films on nickel; of the breakdown of passive films on a wide range of metals and alloys; of the distributions in the breakdown parameters (breakdown voltage and induction time); of the role of alloying elements in enhancing the resistance of alloys to passivity breakdown; of transpassive dissolution and electro‐polishing; of erosion‐corrosion; and of photoinhibition of pit nucleation. Additionally, the PDM has allowed us to formulate a set of principles for designing new alloys and has led to the development of a deterministic method for predicting localized corrosion damage functions.
Abstract The present mechanistic understanding and practical implications of carbon dioxide (CO2) corrosion of carbon and low-alloy steels in hydrocarbon production have been reviewed. This is base... Abstract The present mechanistic understanding and practical implications of carbon dioxide (CO2) corrosion of carbon and low-alloy steels in hydrocarbon production have been reviewed. This is base...
Aqueous solutions of lead salts (1, 2) and saturated Aqueous solutions of lead salts (1, 2) and saturated
Pitting corrosion is localized accelerated dissolution of metal that occurs as a result of a breakdown of the otherwise protective passive film on the metal surface. This paper provides an … Pitting corrosion is localized accelerated dissolution of metal that occurs as a result of a breakdown of the otherwise protective passive film on the metal surface. This paper provides an overview of the critical factors influencing the pitting corrosion of metals. The phenomenology of pitting corrosion is discussed, including the effects of alloy composition, environment, potential, and temperature. A summary is then given of studies that have focused on various stages of the pitting process, including breakdown of the passive film, metastable pitting, and pit growth.
A pit model was developed on the assumption that the metal ions hydrolyze inside the pits and that the corrosion products are transported by diffusion. Concentrations of Me2+, , and … A pit model was developed on the assumption that the metal ions hydrolyze inside the pits and that the corrosion products are transported by diffusion. Concentrations of Me2+, , and H+ ions, as a function of pit depth and current density, for Zn, Fe, Ni, Co, Al, and Cr were calculated. The main reason for passivity breakdown at the initial stages of pit growth, was found to be the localized acidification due to metal ions hydrolysis. Assuming a criticalpH value for pit initiation, the following experimental facts could be explained: (i) the effect of the external pH on the pitting potential of Fe and stainless steel; (ii) the effect of sodium borate concentration on the pitting potential of Zn; (iii) the effect of weak acid salts on the pitting potential of Al; (iv) the oscillations of the electrode potential of stainless steel and nickel in solutions of ions; (v) the existence of a pitting inhibition potential ; and (vi) the existence of a pitting protection potential. Through analysis of the transport processes inside a pit it was also concluded that the pitting potential of a metal should change with the Clāˆ’ ion concentration according to the equation
The self-healing anticorrosion effect of layer-by-layer (LbL) assembled nanoreservoirs (polyelectrolyte-coated nanoparticles) embedded in a hybrid coating deposited onto an Al alloy is investigated (see figure). The corrosion inhibitor, benzotriazole, is … The self-healing anticorrosion effect of layer-by-layer (LbL) assembled nanoreservoirs (polyelectrolyte-coated nanoparticles) embedded in a hybrid coating deposited onto an Al alloy is investigated (see figure). The corrosion inhibitor, benzotriazole, is entrapped in the polyelectrolyte at the LbL assembly step; its release is initiated by local pH changes near the corrosion-damaged zones in the alloy. The nanoreservoirs increase long-term corrosion protection of the substrate and provide effective inhibitor storage and its prolonged release on demand.
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Purpose This paper aims to investigate the corrosion mechanism of X90 pipeline steel under marine alternating dry/wet (ADW) environment and provide a scientific reference for the practical application of X90 … Purpose This paper aims to investigate the corrosion mechanism of X90 pipeline steel under marine alternating dry/wet (ADW) environment and provide a scientific reference for the practical application of X90 grade high-strength low-alloy pipeline steel under marine environment. Design/methodology/approach The finite element analysis was used to determine the stress distribution of C-ring samples. The corrosion resistance of the X90 steel was characterized using the potentiodynamic polarization curve and electrochemical impedance spectroscopy measurements. The surface macroscopic and microscopic morphology of the rust layer were characterized by optical microscope and scanning electron microscope, respectively. The phase composition of the rust layer was characterized using X-ray diffraction. Energy spectrometer was used to detect the element distribution of the C-ring cross-section. Findings The corrosion behavior of X90 steel is affected by the blocking cell effect. The corrosion mechanism of X90 steel is the anodic dissolution dominated and hydrogen evolution assisted. The corrosion behavior of X90 pipeline steel is aggravated with the elongation of ADW cyclic time. Originality/value This study investigated the corrosion mechanism of X90 pipeline steel under marine ADW environment. There is no known scholar who conducted a research on the X90 grade pipeline steel corrosion issue in ADW conditions caused by spray splash zone. What’s more, the spray splash zone is precisely the area where the corrosion rate of metal materials is the fastest in marine environment. This paper can enrich the theoretical research on the corrosion of X90 pipeline steel in marine environment, and provide the theoretical basis for large-scale engineering application of X90 pipeline steel in the future.
Abstract The suppression effect of polyoxyethylene surfactants on the electrochemical deposition of tin (Sn) was systematically studied using cyclic voltammetry and chronopotentiometry methods for future applications for superconducting interconnects in … Abstract The suppression effect of polyoxyethylene surfactants on the electrochemical deposition of tin (Sn) was systematically studied using cyclic voltammetry and chronopotentiometry methods for future applications for superconducting interconnects in quantum devices. Two types of surfactants, igepal with a phenyl group and ENSA with a naphthalene group, were used in conjunction with two simple additives, polyethylene glycol and naphthalene sulfonic acid, to dissect the effects of aromatic ring and the oxyethylene chain. The suppression effect was found to be a result of a synergistic action between aromatic ring and oxyethylene chain. Furthermore, the fused naphthalene ring structure in ENSA results in a stronger adherence to the Sn surface than the single benzene ring in igepal, relating to a stronger and faster suppression that is also more resistant to agitation.
Purpose In this paper, the effects of electro-flocculation of the wastewater obtained from oil refinery distillation unit on the corrosion of three carbon steels and cupronickel alloy were analyzed by … Purpose In this paper, the effects of electro-flocculation of the wastewater obtained from oil refinery distillation unit on the corrosion of three carbon steels and cupronickel alloy were analyzed by electrochemical methods. Design/methodology/approach Samples of each metallic material were individually exposed to wastewater effluent at 0 rpm, 2000 rpm, 20°C, 35°C and 45°C. The metallic materials were exposed to wastewater and evaluated by impedance spectroscopy, polarization curves, scanning electron microcopy and X-ray diffraction (XRD) patterns, before and after the electro-flocculation. Findings 1018 and X52 steels showed higher corrosion resistance in wastewater before and after electro-flocculation at 0 rpm and 35°C, while cupronickel alloy passed to passive and to active state or re-passive process, respectively, after electro-flocculation, at 2000 rpm and 45°C. XRD patterns and electrochemical testing on X80 steel revealed that before electro-flocculation, localized corrosion effect was performed, while after electro-flocculation predominated the general corrosion with evidence of iron sulfides. Practical implications Low carbon steels, such as API steels, as well as cupronickel alloy can be attacked by wastewater, causing serious corrosive problems in refineries equipment and pipelines. The electro-flocculation is a good tool with real application for metallic materials in similar wastewater environments. Originality/value The electro-flocculation of the wastewater is a really important electrochemical treatment for the corrosion control of the refineries equipment and pipelines. It can diminish aggressiveness of corrosive species and semi-protective thin films of iron sulfides might form on metal surface.
Abstract Corrosion is a global concern that leads to significant structural damage and economic losses. Additionally, corrosion control is essential from intellectual, economic, ecological, and aesthetic perspectives. Among various corrosion … Abstract Corrosion is a global concern that leads to significant structural damage and economic losses. Additionally, corrosion control is essential from intellectual, economic, ecological, and aesthetic perspectives. Among various corrosion control techniques, the use of inhibitors remains the most practical, cost‐effective, and efficient method to protect metals from degradation. However, conventional inhibitors such as chromates and sulfates often contain toxic and environmentally hazardous substances, posing serious risks to both human health and ecosystems. In response to these concerns, the development of sustainable and eco‐friendly corrosion inhibitors has gained considerable interest. The increased surface area, distinct physicochemical characteristics, and improved protective capacities of nanomaterial‐based inhibitors have made them attractive substitutes. Recent developments have concentrated on using green synthesis techniques to create ecologically friendly and efficient nanomaterials for corrosion control. This strategy supports sustainable development objectives while reducing the use of dangerous chemicals. Green‐synthesized nanoparticles have been shown in numerous experiments to significantly decrease metal corrosion rates, particularly in hostile environments like acidic solutions. Thus, the combination of green chemistry and nanotechnology presents a promising avenue for creating corrosion inhibitors of the future that are both effective and environmentally friendly. Several nanoparticles, including carbon dots, carbon nanotube hybrid nanoparticles, carbon quantum dots, and nanocomposites, have gained attention for their superior corrosion‐inhibiting capabilities. Nanoparticles strong interactions with metal surfaces lead to the creation of protective barriers. This review highlights the effectiveness and potential for sustainable corrosion control by examining the several nanomaterials as corrosion inhibitors for different metals and also deals with challenges and future aspects of nanomaterials as corrosion inhibitors. Ā© 2025 The Author(s). Journal of Chemical Technology and Biotechnology published by John Wiley &amp; Sons Ltd on behalf of Society of Chemical Industry (SCI).
Purpose The purpose of this study was to fabricate black ceramic coatings on 7050 aluminum alloy via micro-arc oxidation (MAO) at durations of 10, 15, 20 and 25 min. Results … Purpose The purpose of this study was to fabricate black ceramic coatings on 7050 aluminum alloy via micro-arc oxidation (MAO) at durations of 10, 15, 20 and 25 min. Results demonstrated that extended oxidation time (10–25 min) progressively enhanced coating thickness and surface roughness while reducing porosity and structural defects, thereby improving mechanical strength and durability. Among all tested durations, the 20-min MAO coating exhibited optimal performance, achieving the highest hardness (180 HV), lowest porosity (2.584%) and minimal corrosion current density (I corr = 1.214 Ɨ 10 āˆ’7 A/cm 2 ) in 3.5% NaCl solution. Long-term immersion tests confirmed superior corrosion resistance for coatings within this optimized time range. Design/methodology/approach The MAO treatment was performed on 7050 aluminum alloy using a JHMAO-380/20H MAO instrument in a silicate and phosphate electrolyte system with NH 4 VO 3 as a coloring agent. Four different oxidation times were set to prepare the coatings. The microstructure, hardness, tribological properties and corrosion resistance of the coatings were tested and analyzed. Findings At a micro-arc oxidation time of 20 min, the black coating exhibits minimal microcracks and local defects, the lowest porosity, and optimal corrosion resistance, with concurrent peak Vickers hardness (181HV). However,prolonged MAO time increases coating thickness at the expense of reduced corrosion resistence. Originality/value This study systematically analyzes the impact of oxidation time on the properties of black MAO coatings and determines the optimal oxidation time, providing significant insights for the application of MAO technology in the surface treatment of aluminum alloys.
Yuhao Song , Pengjie Wang , Zijie Tang +5 more | Corrosion Engineering Science and Technology The International Journal of Corrosion Processes and Corrosion Control
This study aims to clarify the influence mechanism of pyridine ring substitution position on the performance of imidazolinyl pyridine-based preservatives, linking molecular structure with anti-corrosion performance. Two preservatives, MB2 and … This study aims to clarify the influence mechanism of pyridine ring substitution position on the performance of imidazolinyl pyridine-based preservatives, linking molecular structure with anti-corrosion performance. Two preservatives, MB2 and MB4, were designed. Their anti-corrosion performance and mechanism in 1 mol/L HCl were investigated via weight loss method, electrochemical tests, surface analysis: scanning electron microscope (SEM), energy dispersive X-ray spectroscopy (EDS), X-ray photoelectron spectroscopy (XPS) and theoretical calculations. Results show that at room temperature with 2.00 mmol/L dosage, MB4 achieves 99.08% anti-corrosion efficiency, surpassing MB2's 98.38%. At 313–333 K, MB4's efficiencies (93.96%–86.98%) far exceed MB2's (66.43%–51.82%), proving better temperature stability. SEM/EDS/XPS reveal both form protective films, but MB4's stronger adsorption enhances performance. Quantum chemical calculations show MB4's pyridine-4-aldehyde optimises nitrogen (N) atom electron cloud density for stronger metal interaction. Molecular dynamics (MD) simulations, mean square displacement (MSD) and free volume fraction (FFV) calculations indicate that imidazole rings adsorb on iron first, with carbon chains as hydrophobic barriers. MB4 has lower adsorption energy (āˆ’234.223 vs. āˆ’209.702 kcalĀ·mol āˆ’1 ) and smaller free volume (13.61% vs. 14.24%), inhibiting ion diffusion. The study innovatively demonstrates para-substituted structures enhance efficiency via electronic effects and film compactness, guiding the development of temperature-resistant pickling preservatives.
The current paper examines the sustainable possibility for recycling unused or expired Metoprolol (MET), a benzodiazepine derivative, as an effective corrosion inhibitor for carbon steel in saline solutions. Repurposing expired … The current paper examines the sustainable possibility for recycling unused or expired Metoprolol (MET), a benzodiazepine derivative, as an effective corrosion inhibitor for carbon steel in saline solutions. Repurposing expired medicinal drugs aligns with green chemistry concepts and supports circular economy initiatives by reducing pharmaceutical waste and averting the production of new synthetic inhibitors. The technical benefit of recycling expired MET drugs pertains to the elimination of costs associated with organic inhibitor manufacturing and the decrease in disposal expenses for the expired medication. A combination of electrochemical techniques (potentiodynamic polarization and electrochemical impedance spectroscopy) and quantum chemical calculations was employed to evaluate the inhibitory mechanism and efficacy of MET. At a concentration of 10āˆ’3 M, MET reduced the corrosion current density from 19.38 to 5.97 μA cmāˆ’2, achieving a maximum IE of 69.1%. Adsorption Gibbs free energy, determined using different adsorption isotherms, revealed that interactions between metal atoms and MET adsorbed molecules have a chemical character with a āˆ†Goads value of āˆ’50.7 kJĀ·molāˆ’1. Furthermore, quantum chemistry calculations indicate that the investigated drug, owing to its molecular structure (EHOMO = āˆ’9.12 eV, ELUMO = 0.21 eV, µ = 3.95 D), possesses the capacity to establish an adsorption layer on the metal surface, thereby impeding the diffusion of molecules and ions involved in the overall corrosion process. The results obtained using the different techniques were in good agreement and highlighted the effectiveness of MET in the corrosion inhibition of carbon steel.
Corrosion poses a critical challenge to the durability and performance of metals and alloys, particularly steel, with significant economic, environmental, and safety implications. The corrosion susceptibility of steel is influenced … Corrosion poses a critical challenge to the durability and performance of metals and alloys, particularly steel, with significant economic, environmental, and safety implications. The corrosion susceptibility of steel is influenced by aggressive chemical species, intrinsic material defects, and environmental factors. Understanding the atomic-scale mechanisms governing corrosion is essential for developing advanced corrosion-resistant materials. Density functional theory (DFT) has become a powerful computational tool for investigating these mechanisms, providing insight into the adsorption, diffusion, and reaction of corrosive species on iron surfaces, the formation and stability of metal oxides, and the influence of defects such as vacancies and grain boundaries in localised corrosion. This review presents a comprehensive analysis of recent DFT-based studies on iron and steel surfaces, emphasising the role of solvation effects and van der Waals corrections in improving model accuracy. It also explores defect-driven corrosion mechanisms and the formation of protective and reactive oxide layers under varying oxygen coverages. By establishing accurate DFT modelling approaches, this review provides up-to-date literature insights that support future integration with machine learning and multiscale modelling techniques, enabling reliable atomic-scale predictions.
In this work, micro-arc oxidation (MAO) under constant- and gradient-current modes was used to modify the surface of 6061 aluminum alloy. A black coating was created in situ on the … In this work, micro-arc oxidation (MAO) under constant- and gradient-current modes was used to modify the surface of 6061 aluminum alloy. A black coating was created in situ on the alloy surface by controlling the spark discharge parameters during MAO. Using an electrochemical workstation (Metrohm Autolab, PGSTAT302 N, Herisau, Switzerland), energy-dispersive spectroscopy (EDS, JEOL, JSM-IT500A, Tokyo Metropolis, Japan), and scanning electron microscopy (SEM, JEOL, JSM-7900F, Tokyo Metropolis, Japan), the effects of the current output modes on the coating growth rate, energy consumption, colorimetric parameters (L*, a*, b*), microstructure, and corrosion resistance were methodically examined. The findings showed that the gradient-current mode (6 → 4 → 2 A/dm2) greatly lowered the micropore size (from 3.89 μm to 1.52 μm) and improved the coating compactness (porosity dropped by 40%), and all coatings satisfied the necessary blackness criterion (L* &lt; 30). Additionally, this mode achieved excellent corrosion resistance, as demonstrated by a one-order-of-magnitude reduction in the corrosion current density (2.55 Ɨ 10āˆ’8 A/cm2 vs. 2.34 Ɨ 10āˆ’7 A/cm2), while minimizing the energy consumption (2.37 kWĀ·h/m2·μm vs. 3.45 kWĀ·h/m2·μm for constant current).
ABSTRACT In this paper, the investigation was carried out for the inhibition property of oleic imidazoline quaternary ammonia salt (OIM) as corrosion inhibitor for under‐deposit corrosion (UDC) of X65 steel … ABSTRACT In this paper, the investigation was carried out for the inhibition property of oleic imidazoline quaternary ammonia salt (OIM) as corrosion inhibitor for under‐deposit corrosion (UDC) of X65 steel in CO 2 corrosion environment. Weight loss and In Situ electrochemical measurements were used in an autoclave to study the corrosion behavior of UDC by adding corrosion inhibitor after immersion for a period (pre‐corrosion). The results indicated that adding 50 mg/L of OIM corrosion inhibitor at the initial time (0 h) can achieve the best corrosion inhibition effect, with a corrosion inhibition efficiency of 90.3%. With the delay in OIM adding time, the corrosion inhibition effect gradually weakened. In Situ electrochemical results behaved similar to weight loss. The corrosion product layer displayed differently after 72 h corrosion, the condition of adding OIM at different moments. The surface roughness R a increased with the delay of OIM adding moment, indicating an increase in UDC and reduced protectiveness of layer to the substrate metal. At last, the inhibition mechanism of OIM in the presence of corrosion product layer was proposed.
In this investigation, an alternative Schiff base with a pyrimidine ring was produced through the reaction of (1-amino-4-phenyl-2-thioxo-1,2-dihydropyrimidin-5-yl)(pheĀ­nyl)meĀ­thaĀ­noĀ­ne (1) with thiophene-2-carboxaldehyde. Structural verification of the resulting comĀ­poĀ­und, designated (E)-phenyl (4-phenyl-1-(thiophen-2-ylmethyleneamino)-2-thioxo-1,2-diĀ­hyĀ­droĀ­pyĀ­rimidin-5-yl)methanone, … In this investigation, an alternative Schiff base with a pyrimidine ring was produced through the reaction of (1-amino-4-phenyl-2-thioxo-1,2-dihydropyrimidin-5-yl)(pheĀ­nyl)meĀ­thaĀ­noĀ­ne (1) with thiophene-2-carboxaldehyde. Structural verification of the resulting comĀ­poĀ­und, designated (E)-phenyl (4-phenyl-1-(thiophen-2-ylmethyleneamino)-2-thioxo-1,2-diĀ­hyĀ­droĀ­pyĀ­rimidin-5-yl)methanone, (PPTT), was accomplished by employing a number of specĀ­troscopic methods, including 13C-NMR, 1H-NMR, and FTIR. Open-circuit potential, potentiodynamic polarization, linear polarization resistance, and electrochemical impedance spectroscopy were among the electrochemical methods used to evaluate the efficacy of PPTT as a corrosion inhibitor. After one hour of immersion, experimental data showed that PPTT functioned as a mixed-type corrosion inhibitor, attaining up to 83.8 % inhibition for 2 mM PPTT in 1 M HCl solution. Under these conditions, the corrosion current density dropped from 123.2 to 31.4 μA cm-2. Surface adsorption of PPTT on mild steel in 1 M HCl followed the Langmuir adsorption isotherm, consistent with a negative Gibbs free energy value, indicating both chemisorption and physisorption. In addition, multiple quantum cheĀ­mical parameters (electronegativity, EHOMO, ELUMO, chemical hardness, chemical softness) were calculated using Gaussian 09 to further elucidate the experimental observations.
The research on nontoxic, plant-based corrosion inhibitors has gained momentum in the last few years. Productive uses of fruit waste which comprises of rind, peels and seeds are also being … The research on nontoxic, plant-based corrosion inhibitors has gained momentum in the last few years. Productive uses of fruit waste which comprises of rind, peels and seeds are also being explored as they pose a major problem of waste disposal the world over. Fruit peels can prove to be effective eco - friendly corrosion inhibitors. In this short review some of the fruit peels used for corrosion mitigation for various metals over recent years have been compiled in a tabular form. The techniques used and percentage efficiencies obtained for the maximum inhibitor concentration are also mentioned.
ABSTRACT Cathodic protection (CP) is widely employed to mitigate metal corrosion for underground and marine facilities, but the implementation of conventional sacrificial anode CP (SACP) and impressed current CP (ICCP) … ABSTRACT Cathodic protection (CP) is widely employed to mitigate metal corrosion for underground and marine facilities, but the implementation of conventional sacrificial anode CP (SACP) and impressed current CP (ICCP) is obstructed by drawbacks such as release of harmful substances, continuous external power supply, and complicated maintenance. Although solar‐powered CP systems have emerged to replace conventional systems, the available technical routes are far from perfect: the efficiencies of semiconductor‐based small photoelectrochemical devices are still low, and ICCP systems driven by photovoltaic (PV) cells are often large in size and high in cost. Herein, a portable CP device (30 Ɨ 30 Ɨ 20 cm 3 and 5.1 kg) with a modular design has been constructed, the fully functioning of which is solely powered by a PV cell without any external electricity input. A real‐time ā€œmonitoring‐feedback‐adjustmentā€ mechanism was modulated by a cost‐effective and multifunctional microprocessor to precisely maintain the metal potential within the protective potential range. Moreover, a lab‐made noble‐metal‐free auxiliary anode composed of porous Ni foam coated with NiMo alloy was first introduced to the PV‐driven ICCP system, which accelerated the water oxidation kinetics compared to various commercial anodes and elevated the overall energy efficiency. Consequently, the as‐built SMPCPD was capable of providing continuous CP to three types of representative metals in natural seawater under outdoor sunlight illumination conditions. These findings represent a variable pathway to achieve CP of underwater and underground steel structures with zero carbon emission, no environmental toxicity, intelligent control, high‐energy efficiency, and flexibility.
Abstract Three novel morpholinium-cationic surfactants (coded: DCSM-8, DCSM-10, and DCSM-12) with chemical structure confirmed via FT-IR, HNMR, and mass analysis were applied for carbon steel ( CS ) corrosion control … Abstract Three novel morpholinium-cationic surfactants (coded: DCSM-8, DCSM-10, and DCSM-12) with chemical structure confirmed via FT-IR, HNMR, and mass analysis were applied for carbon steel ( CS ) corrosion control in acidic 4 M HCl solution. The investigated compounds decreased water surface tension (72 mN.m -1 ) to 19.85 mN.m -1 after the addition of DCSM-12. The surfactants mitigation performance was assessed via weight loss ( W L ), potentiodynamic polarization (PDP) and electrochemical impedance spectroscopy (EIS). The synthesized surfactants protected CS efficiently with higher inhibition efficiencies up to 97.029% at 1 Ɨ 10 –3 M for DCSM-12 using PDP which also indicated that, the prepared surfactants inhibited both CS anodic and cathodic sites with cathodic dominant. EIS data showed higher CS resistance from 35.24 Ī©.cm 2 to 1245.54 Ī©.cm 2 after addition of 1 Ɨ 10 –3 M for DCSM-12 with mitigation potency 97.17% which can be attributed to their adsorption process over CS surface forming a protective film layer that followed Langmuir adsorption isotherm reflecting the chemical adsorption affinity of the prepared mitigators with higher adsorption energy (Ī”G* ads ) values (&gt; -40 kJ.mol -1 ). Also, the protection effect of the prepared inhibitor (DCSM-12) was confirmed using SEM (scanning electron microscopy) and EDX (energy-dispersive X-ray) showing improvement in CS surface morphology. The reactivity of the prepared surfactants and their mitigation role in CS deterioration were confirmed theoretically using DFT (density functional theory) and MCs (Monte Carlo simulations).
Abstract Recent works have shown the potential of diatomaceous earth (DE) as an efficient and environmentally friendly storage system for active chemicals such as corrosion inhibitors in coatings. The storage … Abstract Recent works have shown the potential of diatomaceous earth (DE) as an efficient and environmentally friendly storage system for active chemicals such as corrosion inhibitors in coatings. The storage of organic inhibitors is nevertheless challenging. To address this challenge, in this work, we study the effect of surface modification of DE particles on the loading and release of organic corrosion inhibitors in solution and from coatings. To this aim, three trichlorosilanes with varying alkyl chain lengths (C4, C8, C18) were used to modify the surface of sp. Aulacoseira -type diatomite (DE). 2,5-Dimercapto-1,3,4-thiadiazolate di-potassium salts (KDMTD) were selected as a model corrosion inhibitor for its high solubility and effectiveness in protecting Cu-rich aerospace alloys, such as AA2024-T3. UV-Vis spectroscopy revealed a relationship between chain length and inhibitor loading and release, with mid-length silane (C8) adsorbing 3.5 times more inhibitor with no negative effect on release kinetics. When incorporated into epoxy-amine coatings, C8 surface modification significantly improved DE particle dispersion and protection of the inhibitor from the polymer matrix, preventing unwanted side reactions. This increased the availability of active organic inhibitors for protection at damaged sites. In-situ reflected microscopy during immersion and postmortem analysis of damaged coatings demonstrated high levels of corrosion protection and the formation of stable protective layers at damaged sites. The research opens the path to more efficient use of functional DE particles in coatings.
<title>Abstract</title> The response surface methodology (RSM) was used to investigate the influence of benzotriazole (BTA), sulfosalicylic acid (SSA), H<sub>2</sub>O<sub>2</sub>, and temperature on the corrosion resistance of pre-passivation film formed on … <title>Abstract</title> The response surface methodology (RSM) was used to investigate the influence of benzotriazole (BTA), sulfosalicylic acid (SSA), H<sub>2</sub>O<sub>2</sub>, and temperature on the corrosion resistance of pre-passivation film formed on copper. The optimal pre-passivation process was predicted: BTA of 14–16 g/L, SSA of 2-2.3 g/L, H<sub>2</sub>O<sub>2</sub> of 10–11 ml/L, sodium dodecylsulfate of 0.5 g/L and temperature of 45–50ā„ƒ. An improved pre-passivation treatment suitable for B30 alloy, using H<sub>3</sub>PO<sub>4</sub> instead of SSA, showed good corrosion resistance, the polarization resistance increased nearly 100 times in its ā€˜infancy’. In the 30 days of corrosion test, the localized corrosion was significantly inhibited, thus prolonging the service life of the heat-transfer tube.
Presented on 29 May 2025: Session 24 The design consideration for carbon dioxide (CO2) transportation via pipeline from different emitters necessitates the need to develop a CO2 fluid specification at … Presented on 29 May 2025: Session 24 The design consideration for carbon dioxide (CO2) transportation via pipeline from different emitters necessitates the need to develop a CO2 fluid specification at pipeline entry with defined impurity bands, particularly concerning the water (H2O) content. The presence of CO2 can lead to corrosion in carbon steel pipelines. Under-saturated water can also cause pitting corrosion when CO2 interacts with acid-forming impurities. A logic chart that considers CO2 rich mixture fluid components, operating scenarios and water conditions is developed to aid in determining the maximum allowable water content. Fluid components such as triethylene glycol (TEG), even in trace amounts, should not be overlooked as it can decrease the water solubility of CO2 and increase corrosivity in the material. A fine balance should be made when setting the water content specification at pipeline entry as this can influence the choice of the dehydration technology and indirectly affect project economics. To access the Oral Presentation click the link on the right. To read the full paper click here
ABSTRACT This study focuses on the corrosion rate prediction of gas field wellbores. Considering the synergistic effect of corrosion factors such as multiphase flow, temperature, pressure, fluid velocity, pH value, … ABSTRACT This study focuses on the corrosion rate prediction of gas field wellbores. Considering the synergistic effect of corrosion factors such as multiphase flow, temperature, pressure, fluid velocity, pH value, microorganisms, and chloride ions, a CPD‐well multiphase flow corrosion prediction model, which is based on Norsok M506 model, is constructed by utilizing the corresponding parameters of shut‐in wells and production wells. The verification of the predicted corrosion rate is carried out based on MIT logging data of the gas wells. The results show that the determination coefficient R 2 is between 84.6% and 92.1%. To validate the improved quality, a comparison is performed among the CPD‐well, Norsok M506, and De Waard 95 model. Detailed discussions are provided in this study.
This study evaluates the corrosion-inhibiting effects of the methanolic (P1) and the hydroalcoholic (P2) extracts of the Rhus typhina L. leaves on carbon steel (OL37) in 1 M HCl. Extracts … This study evaluates the corrosion-inhibiting effects of the methanolic (P1) and the hydroalcoholic (P2) extracts of the Rhus typhina L. leaves on carbon steel (OL37) in 1 M HCl. Extracts were prepared with microwave-assisted extraction and characterized using HPLC and LC-MS. Electrochemical methods (OCP, EIS, PDP) and surface analyses (SEM, EDX) assessed the performance of both extracts. The results showed that the P1 and P2 extracts significantly reduced corrosion rates by forming protective layers on the metal surface, with inhibition efficiencies exceeding 90%, at 1000 ppm concentration, for P1 (93%), for P2 at 800 ppm (91%) and 1000 ppm (94%). The P2 extract demonstrated superior long-term performance, maintaining protection after 96 h of immersion. The extracts function as mixed-type inhibitors, affecting both anodic and cathodic reactions, with physicochemical adsorption demonstrated by the Langmuir isotherm. Overall, the Rhus typhina leaf extracts, particularly the P2 extract, offer a promising, eco-friendly approach to corrosion prevention in acidic environments.
Owing to the great barrier properties, light weight and environmental friendliness, graphene-based anticorrosion coatings are considered to be promising candidates for next-generation anticorrosion materials. Recently, polydopamine has showed considerable research … Owing to the great barrier properties, light weight and environmental friendliness, graphene-based anticorrosion coatings are considered to be promising candidates for next-generation anticorrosion materials. Recently, polydopamine has showed considerable research value and application prospects in the field of anticorrosion, and provided new opportunities for chemical modification of graphene for the enhancement of coating performance. However, the applications and mechanisms of polydopamine-modified graphene in anticorrosion coatings have not been systematically summarized. This review focuses on the application and mechanism of graphene and polydopamine-modified graphene in anticorrosion coatings. Firstly, the intrinsic barrier properties and applications of graphene in anticorrosion coatings are summarized, especially in self-healing anticorrosion coatings. Next, the properties and applications of polydopamine in the field of anticorrosion are reviewed and discussed. Moreover, the application and mechanism of polydopamine in graphene-based anticorrosion coatings are systematically reviewed, which mainly includes enhancing the intrinsic barrier properties, improving the dispersibility, modifying with functional materials, and introducing pH-responsive properties. Finally, the critical challenges and future prospects for the development of graphene-based anticorrosion coatings are discussed. This article aims to boost further development of graphene-based anticorrosion coatings to solve the anticorrosion bottleneck of equipment in harsh corrosive environments.
This study investigates the synthesis process and characterization methods and evaluates the inhibition behavior of olanzapine (2-methyl-4-(4-methyl-1-piperazinyl)-10H-thieno-[2,3-b] 1,5]benzodiazepine (OLZ)) and its derivatives, such as 3-(2-methyl-4-(4-methylpiperazin-1-yl)-10H-benzo[b]thieno[2,3-e] [1,4]diazepin-10-yl) propenamide (OLZ1) and Ethyl … This study investigates the synthesis process and characterization methods and evaluates the inhibition behavior of olanzapine (2-methyl-4-(4-methyl-1-piperazinyl)-10H-thieno-[2,3-b] 1,5]benzodiazepine (OLZ)) and its derivatives, such as 3-(2-methyl-4-(4-methylpiperazin-1-yl)-10H-benzo[b]thieno[2,3-e] [1,4]diazepin-10-yl) propenamide (OLZ1) and Ethyl 2-(2-methyl-4-(4-methylpiperazin-1-yl)-10H-benzo[b]thieno[2,3-e][1,4]diazepin-10 yl) acetate (OLZ2) for carbon steel (C1018) in a 1 M HCl acidic solution. Fourier Transform Infrared Spectroscopy (FTIR) and Nuclear Magnetic Resonance (NMR) were employed to verify their molecular structures and functional groups, which characterized the derivatives after synthesis. Their corrosion inhibition potential for C1018 steel in acidic media was estimated by weight loss (WL) and electrochemical techniques, such as electrochemical impedance spectroscopy (EIS), linear polarization resistance (LPR), and potentiodynamic polarization (PDP), accompanied by surface analysis methods. The findings revealed that all three derivatives demonstrated exceptional inhibition performance, achieving maximum efficiencies of 88.83%, 91.20%, and 91.82% for OLZ, OLZ1, and OLZ2 at 300 ppm, respectively. Weight loss experiments across different temperatures further explored their inhibitory behavior. Although inhibition efficiency decreased with a temperature increase to 318 K, the derivatives still displayed notable performance, with maximum efficiencies of 74.75% for OLZ, 81.63% for OLZ1, and 79.44% for OLZ2. Polarization studies identified the corrosion inhibition mechanisms as an anodic type. Surface characterization of the C1018 steel coupons, both with and without the inhibitors, was performed using FTIR and scanning electron microscopy (SEM) combined with energy-dispersive X-ray spectroscopy (EDX). These analyses indicated the creation of a protective inhibitor layer on the carbon steel surface, reducing corrosion in the acidic environment. Overall, this study underscores the potential of these drug derivatives as corrosion inhibitors, combining structural insights and performance assessments to support their industrial application.
Abstract The growing demand for cleaner fuel alternatives has driven significant interest in water-in-diesel emulsions to reduce nitrogen oxides and particulate matter emissions, particularly in diesel-dependent regions. However, corrosion of … Abstract The growing demand for cleaner fuel alternatives has driven significant interest in water-in-diesel emulsions to reduce nitrogen oxides and particulate matter emissions, particularly in diesel-dependent regions. However, corrosion of fuel system components remains a critical barrier to water-in-diesel emulsions adoption. This study presents the novel application of ethanol extract of Piper guineense leaves as a green corrosion inhibitor for mild steel in water-in-diesel emulsion environments while also addressing the stability of water-in-diesel emulsion with varying water content, hydrophilic-lipophilic balance, surfactant dosage and mixing time. The anti-corrosion performance was evaluated by immersing mild steel specimens in a water-in-diesel emulsion containing Piper guineense extract at concentrations of 0.5, 1.0, and 1.5 g/L, with weight loss measurements conducted over 672 h. The Piper guineense extract demonstrated a maximum inhibition efficiency of 91.47% at 1.0 g/L, significantly reducing the corrosion rate from 0.0140 to 0.0008 mm/year. Stability evaluation revealed that the maximum emulsion performance was achieved with water-in-diesel emulsion formulated with 20% water content and a 5% surfactant dosage at a hydrophilic-lipophilic balance value of 9, maintaining stability for 8 h without visible phase separation. Surface characterization using Atomic Force Microscopy revealed a 23% reduction in apparent surface roughness and a 28% decrease in overall surface roughness for treated specimens. Fourier-Transform Infrared Spectroscopy analysis identified the adsorption of Piper guineense extract bioactive compounds on the steel surface, forming a protective barrier. These findings highlight the potential of Piper guineense extract as a sustainable additive that enhances material protection while supporting the operational viability of water-in-diesel emulsion fuels.
By encouraging improved adsorption onto metal surfaces and creating a more powerful barrier against corrosive chemicals, the hydrophobic property of corrosion inhibitors raises inhibition efficiency and decreases corrosion rates. This … By encouraging improved adsorption onto metal surfaces and creating a more powerful barrier against corrosive chemicals, the hydrophobic property of corrosion inhibitors raises inhibition efficiency and decreases corrosion rates. This work aims to synthesize and describe three quaternary ammonium-based copolymers (AMCs) with different hydrophobic qualities and investigate their ability to inhibit P110 CS corrosion in 15% HCl, which is helpful for casing and tubing. The results showed that AMCs act as efficient corrosion inhibitors, with over 90% inhibition efficiency ( <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" display="inline" id="M1"><mml:mrow><mml:mspace linebreak="newline"/><mml:mi>%</mml:mi><mml:mi>I</mml:mi><mml:mi>E</mml:mi></mml:mrow></mml:math> ) at 20 ppm concentration. The electrochemical investigation results indicated that the AMCs with hydrophilic and hydrophobic ratios of 100 ( 5 ), 90:10 ( 6a ), and 80:20 ( 6b ) manifest <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" display="inline" id="M2"><mml:mrow><mml:mspace linebreak="newline"/><mml:mi>%</mml:mi><mml:mi>I</mml:mi><mml:mi>E</mml:mi></mml:mrow></mml:math> of 87.74%, 92.12%, and 93.53%, respectively. The electrochemical investigations show that at the metallic surface’s active areas, AMCs successfully replace the pre-adsorbed water molecules. They are categorized as mixed-type corrosion inhibitors because they prevent both anodic and cathodic reactions without appreciably changing the corrosion potential ( <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" display="inline" id="M3"><mml:mrow><mml:msub><mml:mi>E</mml:mi><mml:mrow><mml:mi>c</mml:mi><mml:mi>o</mml:mi><mml:mi>r</mml:mi><mml:mi>r</mml:mi></mml:mrow></mml:msub></mml:mrow></mml:math> ). Their adsorption on the metallic surface follows the Langmuir adsorption isotherm. Surface analysis tools like SEM and EDX are utilized to investigate the corrosion prevention mechanism of adsorption. The DFT analysis results show that quaternary nitrogen atoms of hydrophilic and hydrophobic moieties play a key role in the adsorption and charge-sharing processes. Finally, the corrosion prevention mechanism of AMCs is explained using a graphic depiction based on the ideas of electrochemical, surface, and computational studies.
The adhesion of chlorosulfonated polyethylene (CSM) to aluminum (Al) and its adhesion mechanism was investigated. The lap-shear strength between CSM and Al was nearly 3 times higher than that between … The adhesion of chlorosulfonated polyethylene (CSM) to aluminum (Al) and its adhesion mechanism was investigated. The lap-shear strength between CSM and Al was nearly 3 times higher than that between chlorinated polyethylene (CPE) and Al, suggesting that the chlorosulfonyl (SO2Cl) group enhances the adhesion strength. The CSM-Al interfaces were analyzed using electron energy loss spectroscopy with scanning transmission electron microscopy (STEM-EELS), atomic force microscopy (AFM), and X-ray photoelectron spectroscopy (XPS). The results show that the CSM creates a rough interface with a thick oxide layer containing Al(OH)3 simultaneously in the bonding process. Such an increase in the interfacial roughness is considered to result from the electrochemical reaction of Al mediated by the interaction between the free chloride ions detached from the SO2Cl group and the Al oxide layer. The insoluble adsorbed layers of CSM and CPE on Al were also characterized by ellipsometry. CSM is more likely to contain loosely adsorbed polymer chains. The loosely adsorbed polymer chains behave as connection points between the Al substrate and bulk polymer chains, thereby enhancing the adhesion strength. SO2Cl-containing polymers may offer a new type of adhesive material that does not require surface pretreatment of adherent.
As an insidious and often underestimated phenomenon, microbially influenced corrosion (MIC) poses a significant threat to the integrity and longevity of oil and gas pipelines. However, the complex corrosive microorganisms, … As an insidious and often underestimated phenomenon, microbially influenced corrosion (MIC) poses a significant threat to the integrity and longevity of oil and gas pipelines. However, the complex corrosive microorganisms, that might induce MIC in underground pipelines, might be introduced by the fracturing water during the production period, or they may also exist in the native corrosive microbial community underground. In this study, microbial community analysis was conducted to unravel the source of corrosive microbes in oil and gas pipelines. Meanwhile, the corrosion rate caused by the fracturing water and the flowback water on steel were studied via combining electrochemical analysis and weight loss analysis. Three types of fracturing fluids and the flowback water were analyzed based on 16S rRNA gene sequencing. Bacteria with multiple metabolic functions, including sulfate-reducing bacteria, acid producing bacteria, petroleum oil-degrading bacteria, and nitrate-reducing bacteria, were found in the flowback water. Comparative analysis on the fracturing fluids and the flowback water showed that corrosive Thermodesulfobacterium and DesulfobacterSota originated from the underground rocks. While other microorganisms such as Desulfomicrobium , Acinetobacter and Acetobacterium may be introduced via the fracturing water. The weight loss of steel coupons in fracturing and flowback water were 35.04±7.57 mpy and 28.07±4.49 mpy, respectively. The corrosion weight caused by the fracturing water may accounts for 75.16% of the whole corrosion during the 5 days’ immersion under laboratory conditions. The results provide a reference for tracing the sources of corrosive microorganisms and controlling microbially induced corrosion in shale gas resources.