Corrosion Behavior Of Mild Steel Research Articles

Experiments and Molecular Simulations to Study the Effect of Surface-Active Compounds in Mixtures of Model Oils on CO2 Corrosion during Intermittent Oil-Water Wetting.

Intermittent oil-water wetting can have a significant effect on the internal corrosion of steel pipelines. This paper presents a combined experimental and molecular modeling study of several influential factors on the surface properties and corrosion behavior of mild steel in CO2 environments. The influence of different model oils (LVT-200 and Aromatic-200) and select surface-active compounds (myristic acid, cyclohexane butyric acid, and oleic acid) on the corrosion behavior of carbon steel during intermittent oil-water wetting was determined by measuring the corrosion rate after intermittent wetting cycles. The interfacial tension measurements were performed to study the incorporation of the oil phase along with surface-active molecules in the protective layer formed on the specimen surface. Results showed that the interfacial tension for an aromatic oil-water interface is lower than that for an aliphatic oil-water interface. To understand this result, molecular dynamics simulations of oil-water interfaces were performed in the presence of surface-active molecules and different oils to analyze the structure of the layer formed at the interface. The simulations supported the hypothesis that aromatic molecules are less structured at the interface, which results in the incorporation of more water molecules into the protective layer formed at the steel surface, causing a higher corrosion rate. On the other hand, the simulations revealed that myristic acid in an aliphatic oil forms a well-aligned structure at the interface, devoid of any water molecules. This is in agreement with the hypothesis that the linear molecular structure of myristic acid favors the alignment of molecules at an aliphatic oil-water interface, resulting in a lower interfacial tension and more effective corrosion mitigation as compared to the other two nonlinear compounds tested. It is concluded that an important factor controlling the corrosion behavior is the molecular structure of the oil-water interface, which is adopted by the steel surface layer through the Langmuir-Blodgett process.

Evaluating the performance of corn peptone in preventing the corrosion of mild steel immersed in HCl

AbstractThe effects of biodegradable corn peptone on the corrosion behavior of mild steel in 0.1M HCl were evaluated. The results from the weight loss experiments indicate that changing the amount of corn peptone from 50 to 500 ppm considerably decreased the corrosion rate of the coupons from 28.24 to 4.67 mpy. However, heating the solutions had negative effects on this trend. According to the calculations, dissolving the inhibitor modified the thermodynamic parameters of the corrosion phenomenon. In addition, the adsorption of corn peptone was best fitted with the Langmuir isotherm. The Tafel polarization plots revealed that the presence of corn peptone decreased the corrosion current density from 134.9 to 6.7 µA cm−2. This was compatible with the electrochemical impedance spectroscopy data. Furthermore, X‐ray photoelectron spectroscopy analysis confirmed the adsorption of the tested peptone on the surface of the working electrodes, which based on the atomic force microscope images, reduced the surface roughness of the specimens.

Inhibition of mild steel corrosion by 4-[(benzylidene)-amino]-antipyrine

The inhibition effect of 4-[(benzylidene)-amino]-antipyrine (BAAP) on corrosion behaviour of mild steel in 1 M HCl solution was studied by weight loss, potentiodynamic polarization and electrochemical impedance spectroscopy (EIS) measurements. Polarization measurements indicate that BAAP acts as mixed type of inhibitor. The adsorption of BAAP on the mild steel surface follows Langmuir adsorption isotherm model. The thermodynamic parameters governing the adsorption process were determined and discussed. Also, quantum chemical parameters were calculated to provide further insight into the mechanism of inhibition action of BAAP.

Corrosion behavior of mild steel in 1 M HCl with Cyclotrichium niveum as a green inhibitor

Recently, green inhibitors are replacing classical inhibitors in the acid cleaning industry due to very low cost, environmentally friendly and none toxic. In this study, Cyclotrichium niveum is used as a potential green corrosion inhibitor to investigate the corrosion behavior of mild steel (MS) in chloride solution using electrochemical, morphological, structural and quantum chemical methods. Fifty-three flavonoids are detected in methanol extract of cyclotrichium niveum by LC/ESI-MS/MS. While icorr values decreased, Rp and inhibition efficiencies values derived from electrochemical impedance spectroscopy (EIS) and linear polarization resistance (LPR) increased in increasing inhibitor concentrations. Maximum inhibition efficiency is found to be 97.3%, that is the almost highest value, when compared to previous studies and plant extract is classified as a mixed type inhibitor with respect to the potentiodynamic polarization (PDP). The model that best fits the experimental values is the Langmuir isotherm. The temperature effect is also studied in the range of 25–55 ○C. Higher activation energy is obtained in the presence of inhibitor, suggesting that it acts as an efficient inhibitor by forming a physical barrier to the charge and mass transfer reaction, leading to reduction in corrosion rate. Scanning electron and atomic force microscopies showed the more uniform, crack and pits free structure, confirming that there is a protective film over the MS surface for inhibited solution. XPS analysis showed the existence of C, O, and Fe atoms on the MS surface. Quantum chemical calculation manifested the adsorption mechanism associated with the electronic structure of the molecules. The findings of this work can be applicable in chemical cleaning process with acid treatment.

The synthesis of polyindole-based binder-free coating and its effect on the corrosion behavior of mild steel in 3.5% NaCl solution

The synthesis of polyindole-based binder-free coating and its effect on the corrosion behavior of mild steel in 3.5% NaCl solution

Effect of H2S on CO2 Corrosion of Mild Steel in High-Temperature Supercritical CO2 Conditions

The effect of H2S on the aqueous corrosion behavior of mild steel was evaluated at high-pressure and high-temperature (HPHT) conditions at a partial pressure of CO2 of 12 MPa and a temperature of 160°C. The corrosion rate of steel samples was determined by electrochemical and weight loss measurements. The surface and cross-sectional morphology and the composition of the corrosion product layers were analyzed by using surface analytical techniques (scanning electron microscopy, energy-dispersive x-ray spectroscopy, and x-ray diffraction). Results showed that the corrosion rate decreased with time and no significant difference was observed in the presence of 1,000 ppm and 2,000 ppm of H2S at HPHT CO2 conditions. Surface and cross-sectional analyses revealed that the corrosion process was governed by the formation of FeCO3 regardless of the presence of H2S. Furthermore, the corrosion behavior of mild steel in these conditions did not depend significantly on flow velocity.

Citrus sinensis peel extract as corrosion inhibitor for mild steel in hydrochloric acid solution

This study investigated the corrosion inhibition properties of Citrus sinensis (CS) as a green inhibitor for mild steel in1 M HCl solution at different concentrations (100 mM, 150 mM and 200 mM). The corrosion behaviour of mild steel in the presence of absence of CS was evaluated using weight loss measurement, and scanning electron microscopy (SEM). Results of weight loss measurement showed that the corrosion rate of mild steel in 1 M HCl solution was significantly reduced with increasing concentrations of CS, inhibition efficiency reaching up to 98 %. SEM analysis revealed that the surface of mild steel in the presence of CS was covered a thin and homogenous protective film, while the surface of mild steel without CS was corroded and rough. An isothermal analysis was also carried out and the results indicated that the adsorption of CS on the mild steel surface followed the Freundlich isotherm equation. The value of n was found to be greater than 1, indicating that the adsorption of CS on the mild steel surface was favourable and increased with the inhibitor concentration. The value of the adsorption coefficient (Kf­) was found to be highest at 200 mM of CS, indicating a high adsorption capacity and strength of the CS on the mild steel surface

The anoxic corrosion of mild steel in a cementitious repository environment

AbstractThe long‐term disposal of low‐ and intermediate‐level radioactive waste is anticipated to involve the encapsulation of the material within a cementitious matrix before placement in a deep geological repository. After sealing, the waste repository will become anoxic and the corrosion of emplaced metals will result in the production of hydrogen gas. Knowledge of the rate at which this hydrogen is generated is valuable in that it permits the assessment of pressure build‐up within the repository. The corrosion behavior of mild steel has been monitored through the generation of hydrogen gas, under simulated repository conditions that mimic various stages of cement evolution. It was found that, when cement is used to encapsulate steel, the passage of several years is required for the steel and cement to reach a steady hydrogen production rate. Steel that is directly immersed in simulated cement pore water requires only months to stabilize. All measured steel uniform corrosion rates were significantly below 1 nm year−1 at 50°C, regardless of the test environment, after more than 4 years of exposure.

Investigation of Corrosion Behaviour of Mild Steel Embedded in Geopolymer Paste with Curing and Non-Curing Process

Investigation of Corrosion Behaviour of Mild Steel Embedded in Geopolymer Paste with Curing and Non-Curing Process

ODHI: A promising isatin-based corrosion inhibitor for mild steel in hydrochloric acid

The study aimed to investigate the corrosion behavior of mild steel in acidic environments and to evaluate the effectiveness of an ecofriendly inhibitor named 2-oxo-3-((2,4-dimethoxybenzylidene)hydrazono)indolin (ODHI) derived from Isatin. The researchers employed various techniques such as weight loss, potentiodynamic polarization, electrochemical impedance spectroscopy, and scanning electron microscopy to carry out the experiment in both uninhibited and inhibited 1 M HCl solution at temperatures ranging from 303 to 333 K. The findings revealed that the inhibition efficacy increased with the concentration of ODHI, reaching 94.3% at 0.5 mM in a 1 M HCl solution at 303 K. The results were supported by Density Functional Theory computations, which confirmed the ODHI's corrosion inhibition behavior for mild steel in acidic conditions. The inhibition effect was found to follow the Langmuir isotherm model. Overall, the study demonstrates the potential of ODHI as an effective inhibitor for Mild Steel in acidic environments.

Investigation of Dracocephalum extract based on bulk and nanometer size as green corrosion inhibitor for mild steel in different corrosive media

In recent years, green corrosion inhibitors derived from natural plant resources have garnered much interest. In the present work, at first, we investigated the corrosion behavior of mild steel (st-37) in the presence, and absence of Dracocephalum extract based on bulk size as a corrosion inhibitor in two widely used acidic environments (0.5 M H2SO4, and 1.0 M HCl), at room temperature. Then, we used Dracocephalum extract based on nanometer size to reduce the optimal concentration of inhibitor, increase the corrosion resistant, and efficiency. Dracocephalum extract does not contain heavy metals or other toxic compounds, and also good characteristics such as low cost, eco-friendly, and widespread availability, make it suitable nature candidate as an environmentally safe green inhibitor. The anticorrosive behavior was assessed using electrochemical impedance spectroscopy (EIS), and potentiodynamic polarization (PP). In all of the studies, the inhibitory efficiency (IE%) increased as the extract dose was increased. But by using nano extract, in addition to maintaining high efficiency, the amount of inhibitor was reduced significantly. The highest IE% is 94% at the best dose of nano extract (75 ppm), but the highest IE% is 89% at the best dose of the bulk extract (200 ppm) in H2SO4 solution. Also, for the HCl solution, the highest IE% is 88% at the best dose of nano extract (100 ppm), but the highest IE% is 90% at the best dose of the bulk extract (400 ppm), by polarization method. The PP results suggest that this compound has an effect on both anodic, and cathodic processes, and that it adsorbs on mild steel surface according to the Langmuir adsorption isotherm. Optical microscopy, scanning electron microscopy (SEM) analysis, and a solid UV–Visible reflection spectrum were used to investigate the alloys' surface morphology.

Investigational and Conceptual Study of HCl-H2CRO4 Acid Mixture towards Corrosion Behavior of Mild Steel Using Chemical and Polarization Methods

Investigational and Conceptual Study of HCl-H2CRO4 Acid Mixture towards Corrosion Behavior of Mild Steel Using Chemical and Polarization Methods

New developed for generating superhydrophobic surface modification on mild steel for corrosion protection

The synergism effect of sodium tartrate and Zn2+ binary inhibitor system on the corrosion inhibition efficiency of mild steel in an potable water medium containing was analyzed by means of gravimetric and electrochemical spectroscopic measurements. The effect of weight loss method and immersion time on the corrosion behavior of mild steel has also been studied. The scanning electron microscopic (SEM) images showed that the roughness and the deep cracks of the metal surface are reduced significantly by the inhibitor system. Results indicated that the formulation acted as anodic inhibitor. Adsorption of used inhibitor lead to a decrease in the double layer capacitance and an increase in the charge transfer resistance and confirm protective layer by SEM, EDX, AFM and FT-IR. Simple and novel binary inhibitors approach was developed for generating superhydrophobic surface modification of mild steel. Interestingly, Water droplets falling on the leaves bead up and roll off, mild steel immersed in potable water in the presence of binary inhibitor system (sodium tartrate and Zn2+) was attempted to create superhydrophobic surfaces. However, the water contact angle in presence of binary inhibitor system was found to be 152°±4°, whereas in the case of mild steel, it was 55°±2°. A detailed description of the surface-modified superhydrophobic in potable water on mild steel is presented in this article.

Corrosion Behavior of Mild Steel in the Presence of Urea, Sodium Chloride, Potassium Chloride, and Glycine: A Kinetic and Potentiodynamic Polarization Study Approach

Corrosion Behavior of Mild Steel in the Presence of Urea, Sodium Chloride, Potassium Chloride, and Glycine: A Kinetic and Potentiodynamic Polarization Study Approach

He Effect of Cooling Media on the Corrosion Behavior of Mild Steel after Heat Treatment

When creating structural molds and automobile parts, mild steel is employed in a number of technical applications. However, the material experiences corrosion when it is exposed to the environment and this leads to large economic impacts for applications using the metal. This research work discusses the effect of cooling media (water, air and oil) on the corrosion assessment of mild steel after heat treatment. The temperature for the polarization experiments was 260C, and the immersion periods ranged from one day (24 hours) to twelve days (288 hours). It was discovered that when the open circuit potential (OCP) measurement was carried out in the mild steel samples before heat treatment, the value initially changed to 0.0192 V, this then moved towards the negative to a value of -0.3716 V. The results show that in samples heat treated at 5000C, the efficiency is lower than when the temperature is increased to 9000C, where an improvement in efficiency is observed.

Thermodynamic Investigation of Leptadenia Hastata (Yadiya) Leaves Extract on Corrosion Inhibition of Mild Steel in Acidic Media

The inhibiting effect of Leptadenia hastata (Yadiya) leaves extract on corrosion inhibition of mild steel in acidic media was studied by thermo gravimetric techniques. Three temperatures ranging from 313 K – 333 K with interval of 10 ºC were used to study the effect of temperature on corrosion behavior of mild steel. The thermodynamic parameters and the values of free energy of adsorption for investigated extract were calculated and discussed. The results show that inhibition efficiency increases with increasing the inhibitor concentration, which is attributed to the presence of phytocompounds in the extract. On the other hand, the decrease of inhibition efficiency with increase in temperature indicates the adsorption to be chemisorption. The adsorption of the extract on the mild steel surface obeys the Langmuir adsorption isotherm. It was found that the adsorption increases, in the same direction as inhibition efficiency. The results obtained depict the influences of temperature and its effects on corrosion control in acidic medium.

Metronidazole and 2-Methylimidazole as Corrosion Inhibitors in Microbiologically Influenced Corrosion

Microbial corrosion behavior of mild steel was studied by exposing mild steel coupons in Barr’s medium inoculated with sulfate-reducing bacteria (Desulfovibrio desulphuricans). During the investigation, a considerable loss in weight and deterioration of microstructure of mild steel coupons surface was observed. Coupons were further exposed to culture media containing different concentrations of metronidazole (MNZ) and 2- methylimidazole (MIZ) inhibitors. The corrosion behavior of mild steel was measured by weight loss, electrochemical studies, and SEM. Polarization studies indicated the mixed-type behavior of these inhibitors. MNZ and MIZ exhibited 82.23 and 78.30 % inhibition efficiencies, respectively, as revealed by polarization measurements. The results show that the inhibition efficiencies increased with inhibitor concentration. The surface analysis was performed by scanning electron microscopy (SEM).

Corn starch inhibitive evaluation on marine corrosion of mild steel

Corrosion is a essential process that has a significant economic and safety impact. Corrosion cannot be avoided, but its severity can be prevented. Inhibitors have always been considered to be the first line of defense against corrosion. This research focuses into the usage of maize starch tapioca to improve mild steel corrosion inhibitors in seawater. The corrosion behaviour of mild steel in saltwater was investigated using gravimetric, potentiodynamic polarisation, and linear polarisation resistance measurements. The addition of maize starch greatly reduces the corrosion rates, corrosion current densities (icorr), and corrosion rates twofold (CR) in mild steel in seawater, while concurrently boosting the values of polarisation resistance (Rp). As the concentration of maize starch rises, so does the efficiency of inhibition. The prospective application of maize starch addressed in this study is in keeping with the current trend of environmentally responsible thinking.

The Influence of REE β-Diketone Complexes on the Corrosion Behaviour of Mild Steel and 304 SS in 3.5% NaCl Solution

In the present investigation, four REE β-diketone complexes, namely cerium acetylacetone, cerium hexafluoroacetylacetone, lanthanum acetylacetone, and lanthanum hexafluoroacetylacetone, were investigated as potential corrosion inhibitors for mild steel and 304 stainless steel in 3.5% NaCl solution. The corrosion-inhibition effects of the REE β-diketone complexes were investigated using weight-loss measurements and potentiodynamic polarisation scans. Surface analyses using optical microscopy and scanning electron microscopy (SEM) were used to investigate the morphology of the mild steel and 304 stainless steel after the weight-loss and potentiodynamic tests in 3.5% NaCl solution containing 0.5% mass per volume (m/v) concentration of the tested inhibitor. Fourier transform infrared spectroscopy and Raman spectroscopy were further used to probe the type of corrosion product film that forms on the surface of the tested samples. The obtained results revealed that the four REE β-diketone complexes are very effective inhibitors against corrosion of mild steel and 304 stainless steel in a 3.5% NaCl in a temperature range of 20–60 °C.

Effect of corrosion rates of preheated Schinzochytrium sp. microalgae biodiesel on metallic components of a diesel engine

Hitherto, the myriad of researches conducted on biofuels coupled with their poor oxidative stabilities, show that none of these studies has considered monitoring the corrosive effects of Schinzochytrium sp. microalgae biodiesel on diesel engines. In this study, corrosion behaviors of mild steel (MS), aluminum (Al) and copper (Cu) were compared via immersion tests in preheated schinzochytrium sp. microalgae biodiesel and its blends at room temperature and 60 °C for 1200 h. Property-variation of the individual/blended fuels, corrosion rates/products of the metals, and their morphologies were examined. For the metals, the corrosion rates are in the order of Al < MS < Cu at room temperature and 60 °C. The degraded properties and corrosion rates of the metals in the diesel fuel (B-100) and biodiesel fuel-blends, were seen to be minimal relative to those of neat biodiesel (D-100). The morphologies of the metals in contact with the fuels, showed substantial variation in surface properties for the Al, MS and Cu specimens. Furthermore, of all the three metals, copper was most prone to biodiesel corrosion. Hence, the results suggest the need to anticipate a future where the use of corrosion inhibitors for preventing engine-part degradation induced by biofuels becomes a reality.