Organic Corrosion Inhibitors Research Articles

Electrodeposition of organic corrosion inhibitor prepared from eucalyptus robusta leaves

Eucalyptus Robusta leaves were used as raw material to develop a steel corrosion inhibitor. A straightforward approach was employed to extract organic molecules from Eucalyptus Robusta leaves, which were applied as a protective coating on steel surfaces to inhibit corrosion. The solution containing the organic inhibitor was electrodeposited onto the surfaces of ASTM A36 steel samples, and an investigation into the parameters of charge (positive or negative), voltage (5 or 20 V), and time (5 and 30 min) was conducted through a 23 factorial experiment. Electrodeposited wet and dry samples had their open circuit voltage (OCP) measured in an acid solution and compared with the OCP of samples in which the inhibitor was deposited by simple immersion (deposited samples) and samples without inhibitor (blank samples). All the samples that had contact with the inhibitor increased their OCP values, showing the effectiveness of the deposition of the inhibitor. Nevertheless, the electrodeposition process carried out for 30 min and with a positive charge (anodic) proved to be the most effective in increasing the OCP value. Optical and scanning electron microscopy analyses revealed that the inhibitor solution effectively formed a thin, uniform, compact film on the metal surface. However, occasional deposition anomalies resulted in the formation of protrusions with organic material accumulation. Electrochemical Impedance Spectroscopy and Tafel curves were used to evaluate the effectiveness of the organic inhibitors. Accelerated corrosion tests in an HCl solution indicated reduced corrosion and the formation of distinct corrosion products for samples with an inhibitor compared to a sample without an inhibitor.

Effects of –NH2 and –COO− functional groups on the steel passivation in concrete pore solution: Passivation performance and interfacial adsorption mechanism

The use of organic corrosion inhibitors is a common method for enhancing the corrosion resistance of steel in concrete. Whereas, the effects of common functional groups (–NH2 and –COO−) on the steel passivation are still unclear. Herein, propylamine (C3H7NH2) and calcium butyrate ((C3H7COO)2Ca) were selected as representative inhibitors containing –NH2 and –COO− groups, respectively. The passivation performance of steel affected by C3H7NH2 or (C3H7COO)2Ca in simulated concrete pore solution was explored by electrochemical method, XPS tests, and DFT simulation. Experimental results show that the (C3H7COO)2Ca has little effect on passivation performance, while the C3H7NH2 exhibits an inhibition effect. The XPS data shows that the (C3H7COO)2Ca decreases the Fe/Fen+ ratio on the steel surface, thereby enhancing the physical protectiveness of passive film. Although the C3H7NH2 causes an increase in the chemical protectiveness of passive film (Fe2+/Fe3+ ratio increase), it induces a more pronounced decrease in physical protectiveness, resulting in the poor passivation performance of steel. DFT results indicate that the C4H7O2− adsorption increases the activity of iron surface, thereby promoting the adsorption of passivation substances (OH–/CaOH+). Moreover, insoluble C4H7O2-Ca-Fe compounds form due to the electron transfer between –COO− and CaOH+. Besides, the C3H7NH2 inhibits the adsorption of OH–/CaOH+ on steel surface.

An investigation of modified dialdehyde starch as a highly efficient green corrosion inhibitor for carbon steel in 1 M HCl medium: Synthesis, experimental and theoretical studies

Compared to small organic molecule corrosion inhibitors, polymer corrosion inhibitors offer numerous advantages in terms of adsorption coverage on the metal surface and the presence of multiple active sites for adsorption. A dialdehyde starch Schiff base was synthesized by modification of natural polymer starch and tetraethylene pentaamine, and it was characterized by X-ray diffraction, gel chromatography and thermogravimetry. The corrosion inhibition behaviors of dialdehyde starch Schiff base as an oligomer for low carbon steel in 1 M HCl were investigated. Compared to the common starch derivatives, the dialdehyde starch Schiff base has good water solubility and inhibition performance. The inhibition efficiency can reach 93.2% with 0.16 mM in 1 M HCl solution at 333 K. Double aldehyde starch Schiff base is a mixed corrosion inhibitor that mainly inhibits cathodic reactions. Its adsorption on the surface of carbon steel follows the Langmuir adsorption equation, and the nitrogen -containing groups in the molecules are adsorbed on the surface of the steel through physical and chemical reactions. Quantum chemical calculations confirmed the experimental results.

Effect of organic corrosion inhibitors functional groups (azo and azomethine) on carbon steel N80 alloy corrosion using the electrochemical polarization technique

Effect of organic corrosion inhibitors functional groups (azo and azomethine) on carbon steel N80 alloy corrosion using the electrochemical polarization technique

Understanding the mechanism of organic corrosion inhibitors through density functional theory

Abstract Organic corrosion inhibitors have been widely used to prevent and mitigate the damaging effects of corrosion on metal surfaces. However, their underlying mechanisms of action and effectiveness are still not fully understood. In recent years, the use of density functional theory (DFT) has emerged as a powerful tool to investigate the interaction between organic inhibitors and metal surfaces at the molecular level. This review article provides an overview of the principles of DFT, its advantages and limitations, and its application to the study of organic corrosion inhibitors. The factors affecting the performance of organic inhibitors, such as molecular structure, functional groups, and metal surface properties, are discussed in detail. The interaction between organic inhibitors and metal surfaces, including the adsorption and desorption of inhibitors, the role of intermolecular forces, and the effects of pH and temperature, are also explored. Finally, the challenges and future directions in the development of organic inhibitors using DFT are highlighted, including limitations and challenges in using DFT and potential avenues for further research. Overall, this review demonstrates the potential of DFT to provide valuable insights into the mechanism of organic corrosion inhibitors and to guide the development of new and more effective inhibitors for the protection of metal surfaces.

Electrochemical and surface analysis investigation of corrosion inhibition performance: 6-Thioguanine, benzotriazole, and phosphate salt on simulated patinas of bronze relics

Organic heterocyclic corrosion inhibitors play a crucial role in the non-destructive protection of excavated bronze relics exposed to the atmosphere. However, the current selection of corrosion inhibitors, additives, and dosage requires further investigation. This study involves a comprehensive preparation simulation of electrode materials and atmospheric corrosion electrolytes. The corrosion inhibition performance of 6-thioguanine (6-Tg) and traditional benzotriazole (BTA) inhibitors at pH = 7.5 is explored. Analytical techniques such as potentiodynamic polarization, EIS, XRD, XPS, and SEM-EDS were employed to analyze the characteristics of the research electrode materials. Surface analysis reveals that 6-Tg forms a protective corrosion inhibition film on the surface of the covered patina electrode, influencing the transition of Cu2(OH)3Cl to the more stable Cu2(OH)2CO3 crystal. Electrochemical results demonstrate that, after 600 h in the corrosion solution containing 0.1 g/L of 6-Tg, the corrosion potential and corrosion current reach 0.244 V and 4.9 μA cm−2, respectively. Upon adding 1.2 g/L of NaH2PO4, the polarization resistance and inhibiting efficiencies reach 15.6 kΩ cm2 and 99%, resulting in a synergistic corrosion inhibition effect and passivation potential shift from −0.6 V to 0.2 V region.

Soybean and Glycine as Potential Corrosion Inhibitors for Steel in Hydrochloric Acid: Electrochemical and Morphological Studies

The potential of soybean and glycine as organic corrosion inhibitors for steel in acid solution was examined through weight loss tests and potentiodynamic polarization. Both soybean and glycine were characterized via FTIR and UV-visible. The result shows that the soybean and glycine contain isoflavone and nitrogen bonds respectively as a beneficial element in inhibiting the corrosion of steel. Corrosion tests were performed with and without the presence of soybean and glycine for 3 days of immersion in the acidic medium. Corrosion inhibition efficiency measured via electrochemical test found that both soybean and glycine give an excellent corrosion inhibition efficiency at 1.5 g/L in 0.5 M HCl up to 96% and 94% respectively. Tafel analysis reveals both inhibitors perform mixed types inhibitors which predominantly anodic inhibition. Pseudo-passivation was observed in the Tafel curve indicating the capabilities of both inhibitors to passivate the corrosion at anodic potential. Observation of the steel samples through an optical microscope shows that the corrosion of the steel surface was inhibited in the addition of soybean and glycine in HCl. The roughness of the steel surface affected by the combination of uniform and pitting corrosion was also reduced. In overall, soybean and glycine exhibit excellent anticorrosive properties due to the presence of significant chemical structures and active functional groups. Analysis of the inhibition mechanism through isotherm showed that soybean and glycine followed Langmuir isotherm, indicating the adsorption type for both inhibitors is chemisorption. The results obtained from this study could be a good reference in diversifying the study of amino acids as metal corrosion inhibitors to benefit metal-based industries.

Eco-Friendly Sol-Gel Coatings with Organic Corrosion Inhibitors for Lightweight AZ61 Alloy.

The latest advances in technology and materials science have catalyzed a transformative shift towards the adoption of environmentally conscious and lightweight materials across key sectors such as aeronautics, biomedical, and automotive industries. Noteworthy among these innovations are the magnesium-aluminum (Mg-Al) alloys employed in aeronautical applications, contributing to the overall reduction in aircraft weight and subsequently diminishing fuel consumption and mitigating atmospheric emissions. The present work delves into a study of the anti-corrosive properties inherent in various sol-gel coatings, leveraging a range of environmentally friendly corrosion inhibitors, specifically tailored for samples of the AZ61 alloy. Methodologically, the work involves the synthesis and application of sol-gel coatings on AZ61 alloy containing eco-friendly inhibitors: L-cysteine, N-acetyl-cysteine, curcumin and methylene blue. Subsequently, an accelerated corrosion test in a simulated saline environment is performed. Through microstructural and compositional analyses, the best inhibitors responses are achieved with inhibitors containing S, N heteroatoms and conjugated double bonds in their structure, probably due to the creation of a continuous MgCl2 layer. This research contributes to the ongoing discourse on protective eco-coatings, aligning with the broader paradigm shift towards sustainable and lightweight materials in key industries.

Synthesis and investigation of two new compounds (2-(methoxymethyl)−1- phenyl-2-propen-1-one and 2-(methoxymethyl)−1-(4-methoxyphenyl) - 2-Propen-1-one) as corrosion inhibitors for mild steel in acidic solutions at elevated temperature.

This study evaluated the performance of two newly synthesized organic corrosion inhibitors using the gravimetric weight loss method in hydrochloric acid (HCl), methanesulphonic acid (MSA), and a combination of HCl and MSA in the presence of different corrosion inhibitor (CI) concentrations at temperatures of 30 °C to 90 °C. Potentiodynamic polarization (PDP) and electrochemical impedance spectroscopy (EIS) studies were carried out for an in-depth study of corrosion mechanisms. Following the weight loss study, the percentage inhibition efficacies of C1 and C2 at 300 ppm concentrations were found to be ≈ 100% at 30 °C, 40 °C and 60 °C in 15 wt% HCl, 10 wt% MSA, and a combination of both acids (15 wt% HCl and 10 wt% MSA). The performances of C1 and C2 deteriorated slightly when tested in 10 wt% MSA at 90 °C. The synthesized CIs still showed a very high inhibition efficiency in the presence of 15 wt% HCl and a mixture of acids (HCl and MSA) at 90 °C. PDP studies indicated that both C1 and C2 act as anodic inhibitors. The inhibition efficiencies obtained from the PDP and EIS studies agreed with the weight loss study. The high value of Kads and the negative ∆Gads value suggests that C1 and C2 corrosion inhibitors have a strong and spontaneous tendency to chemisorb onto the mild steel surface. SEM-EDX studies proved the formation of a uniform, protective corrosion inhibitor film on the metal surface. Both C1 and C2 have been proven suitable for high-temperature corrosion applications.

Anticorrosive action of eco-friendly plant extracts on mild steel in different concentrations of hydrochloric acid

Abstract The extracts of different parts of plants (leaf, stem, and flower) act as a green, environmentally friendly, economical, and safe corrosion inhibitors. The eco-friendly extracts of plant material provide an excellent alternative that substitutes toxic traditional (organic and inorganic) corrosion inhibitors. The plant extracts are renewable and readily available; thus, they occupy a unique position in the family of green inhibitors. The plant extract contains several bioactive compounds, such as flavonoids, tannins, polyphenols, phenolic acids, glycosides, flavonols, etc., which possess experienced significant interest as anti-corrosive agents. These plant extracts contain several heteroatoms like phosphorus, nitrogen, sulfur, oxygen, etc., which are adsorbed on the metallic surface and form an inert protective layer that protects metal from a corrosive environment. Thus, this article aims to shed light on the efficiency of plant extract in protecting steel in an acidic environment.

Effect of Organic Corrosion Inhibitor on Mechanical and Transport Properties of concrete

In this paper, the effect of organic corrosion inhibitors on Mechanical and Transport Properties of concrete was studied. Two types of organic inhibitors, one is added to the concrete mix (sika Ferrogard®-901), and another one applied on the concrete surface (sika Ferrogard®-903. The properties of the fresh concrete (workability and air content) and of the hardened concrete (compressive strength, Porosity, and water absorption) were evaluated. The transport properties (permeability, capillary absorption, and diffusion) were also evaluated. From the results, it was found that the effect of the organic inhibitor (Ferrogard®-901) was clear on the properties of fresh concrete. so that Workability increased with the addition of organic corrosion inhibitors. The effect of (OCI) on the compressive strength at all ages was not significant. The effect of organic inhibitors on the porosity of concrete was also not significant, although the porosity of the samples with Ferrogard®-901 was lower. As for the permeability test, both samples containing (sika Ferrogard®-901) and (sika Ferrogard®-903) outperformed the control sample. In addition to the clear effect of (sika Ferrogard®-901) in reducing the permeability. Both organic inhibitors affected the diffusion and capillary absorption of concrete.he

Effect of Organic Corrosion Inhibitors on the Kinetics of the Cathodic Hydrogen Evolution Reaction on Steel in a Sulfuric Acid Solution

Effect of Organic Corrosion Inhibitors on the Kinetics of the Cathodic Hydrogen Evolution Reaction on Steel in a Sulfuric Acid Solution

Functionalization of Plasma Electrolytic Oxidation/Sol–Gel Coatings on AZ31 with Organic Corrosion Inhibitors

In this investigation, the sol–gel method is employed along with a corrosion inhibitor to seal a plasma electrolytic oxidation (PEO) coating, aiming to improve the long-term corrosion resistance of the AZ31 Mg alloy. Following an initial screening of corrosion inhibitors, 8-hydroxyquinoline (8HQ) is incorporated into the hybrid PEO/sol–gel system using two methods: (i) post-treatment of the PEO layer through immersion in an inhibitor-containing solution; (ii) loading the inhibitor into the sol–gel precursor. The characterization includes scanning electron microscopy (SEM), X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR), ultraviolet-visible spectroscopy (UV-vis), and water drop contact angle measurements. The rheological properties of the inhibitor-loaded sol–gel precursors are assessed by measuring flow curves. The corrosion processes are evaluated in a saline solution through electrochemical impedance spectroscopy (EIS) and immersion tests with unscratched and scratched specimens, respectively. The results demonstrate the successful incorporation of the inhibitor for both loading strategies. Regardless of the loading approach, systems containing 8HQ exhibit the most favourable long-term corrosion resistance.

Current and emerging trends of inorganic, organic and eco-friendly corrosion inhibitors.

Effective corrosion control strategies are highly desired to reduce the fate of corrosion. One widely adopted approach is the use of corrosion inhibitors, which can significantly mitigate the detrimental effects of corrosion. This systematic review provides a thorough analysis of corrosion inhibitors, including both inorganic and organic compounds. It explores the inhibition mechanisms, highlighting the remarkable inhibitive efficiency of organic compounds attributed to the presence of heteroatoms and conjugated π-electron systems. The review presents case studies and investigations of corrosion inhibitors, shedding light on their performance and application potential. Moreover, it compares the efficacy, compatibility, and sustainability of emerging environmentally friendly corrosion inhibitors, including biopolymers from natural resources as promising candidates. The review also highlights the potential of synergistic impacts between mixed corrosion inhibitors, particularly organic/organic systems, as a viable and advantageous choice for applications in challenging processing environments. The evaluation of inhibitors is discussed, encompassing weight loss (WL) analysis, electrochemical analysis, surface analysis, and quantum mechanical calculations. The review also discusses the thermodynamics and isotherms related to corrosion inhibition, further improving the understanding of inhibitor's behavior and mechanisms. This review serves as a valuable resource for researchers, engineers, and practitioners involved in corrosion control, offering insights and future directions for effective and environmentally friendly corrosion inhibition strategies.

Using Lignin and Tannin as Green Corrosion Inhibitors for Carbon Steel Petrolum Tanks

The best strategy for combating corrosion is verified by recent studies that employ organic green corrosion inhibitors isolated from plant extracts that are biodegradable, environmentally friendly, suitable priced, and safe. This current research conducted various experiments on Kraft lignin extracted from Iraqi date palm fronds base (DPFB) and tannin to inhibit corrosion. The corrosion monitoring technique includes the weight loss method and surface analysis by optical microscope. The extracted lignin was characterized using 13CNMR. The results showed clear evidence of Kraft lignin’s and tannin's corrosion inhibition behavior of carbon steel alloys immersed in 0.5 M HCl solutions. As increasing concentration, Kraft lignin and tannin became more effective inhibitors. Furthermore, Kraft lignin showed more effectiveness as a corrosion inhibitor than tannin.

Anticorrosive performance of thiophene-based inhibitor-reinforced PVB coating on mild steel: an inclusive approach to the structural advantage of corrosion inhibitors

This paper highlights importance of structural design in achieving high-performance organic corrosion inhibitors and provides a novel pathway for developing eco-friendly solutions for corrosion prevention in various industries.

Relative Comparison of Adsorption and Corrosion Inhibition Studies of Expired Vitamin B12 and C Over Mild Steel in 0.5 M H2SO4

In comparison to organic corrosion inhibitors, green corrosion inhibitors are in great need for mitigating corrosion of metals and alloys ascribed to their benign toxicity in addition to absence of heavy metals and toxic substances. Contemporary research conducted in this field is more focused on implementing an efficient approach towards corrosion mitigation. The present work highlights the evaluation of anti-corrosive potential of expired Vitamin B and Vitamin C over mild steel in 0.5M H2SO4. Gravimetric and electrochemical studies have been utilized as affirmatory tool for corrosion retarding ability of the synthesized derivative. Concentration increase brought a profound rise in corrosion inhibition efficiency whereas variation in temperature from 308 K-328 K retarded the protection ability of respective inhibitors whereas electrochemical studies presented depressed semi-circles in Nyquist plots and potentiodynamic values demarcated both inhibitors as mixed type. Furthermore, a comparison among the two tested vitamins has been drawn. Contact angle measurements have been involved here to confirm the inhibitors adsorption over mild steel surface. The present experimental work will provide future insights for researchers working in field of corrosion.

Stabilization of zinc anode by trace organic corrosion inhibitors for long lifespan

Stabilization of zinc anode by trace organic corrosion inhibitors for long lifespan

Corrosion inhibitor screening for AA6014 aluminum alloy under different ambient conditions using a novel multielectrode methodology

A novel electrochemical cell to assess the effectiveness of organic corrosion inhibitors in preventing droplet corrosion for alloy AA6014. The study focuses on analysing the impact of pH and inhibitor chemical structure on their performance.

A data-driven QSPR model for screening organic corrosion inhibitors for carbon steel using machine learning techniques.

Machine learning (ML) techniques have shown great potential for screening corrosion inhibitors. In this study, a data-driven quantitative structure-property relationship (QSPR) model using the gradient boosting decision tree (GB) algorithm combined with the permutation feature importance (PFI) technique was developed to predict the corrosion inhibition efficiency (IE) of organic compounds on carbon steel. The results showed that the PFI method effectively selected the molecular descriptors most relevant to the IE. Using these important molecular descriptors, an IE predictive model was trained on a dataset encompassing various categories of organic corrosion inhibitors for carbon steel, achieving RMSE, MAE, and R2 of 6.40%, 4.80%, and 0.72, respectively. The integration of GB with PFI within the ML workflow demonstrated significantly enhanced IE predictive capability compared to previously reported ML models. Subsequent assessments involved the application of the trained model to drug-based corrosion inhibitors. The model demonstrates robust predictive capability when validated on available and our own experimental results. Furthermore, the model has been employed to predict IE for more than 1500 drug compounds, suggesting five novel drug compounds with the highest predicted IE on carbon steel. The developed ML workflow and associated model will be useful in accelerating the development of next-generation corrosion inhibitors for carbon steel.