Corrosion Inhibition Performance Research Articles

Corrosion inhibition performance of expired amlodipine on cupronickel alloy in a neutral chloride environment: electrochemical and surface analysis

Purpose The corrosion of cupronickel and copper alloys in marine and chloride environments presents significant challenges in the chemical and petrochemical industries. This paper aims to investigate the corrosion inhibition of cupronickel alloy (Cu-10Ni) in a sodium chloride medium using expired amlodipine as a corrosion inhibitor. The use of this drug in its expired form could reduce the costs of corrosion and help mitigate the accumulation of pharmaceutical waste. Design/methodology/approach The inhibitory action was evaluated using a weight loss method, potentiodynamic polarization, electrochemical impedance spectroscopy measurements, scanning electron microscopy (SEM) and atomic force microscopy (AFM). The effect of temperature on the inhibition performance was also studied. Findings The results of these experiments demonstrated that the drug amlodipine effectively inhibited the corrosion of cupronickel alloy in chloride solutions. The corrosion rate of cupronickel was found to decrease with increasing inhibitor concentration and to increase with rising temperature. A maximum inhibition efficiency of 91.92 was achieved with an inhibitor concentration of 0.025 g/L at 298 K. Adsorption of the inhibitor followed the Langmuir adsorption isotherm. Polarization studies indicated that the expired drug acted as a mixed inhibitor. SEM and AFM analyses confirmed that the surface morphology of cupronickel specimens was significantly improved in the presence of the inhibitor. Practical implications Amlodipine can be conveniently used to mitigate problems with the corrosion of copper alloys in chloride environments. Originality/value Amlodipine is evaluated as a novel and effective corrosion inhibitor for cupronickel alloy in neutral chloride environments.

Evaluation of cactus mucilage as a green corrosion inhibitor for copper in sulfuric acid environment

This study investigates the corrosion inhibition performance of cactus mucilage for copper in 0.5 M H2SO4 solution. The cactus mucilage was extracted using a pure water extraction method and characterized using FTIR and GC-MS analyses. The inhibition efficiency was evaluated using potentiodynamic polarization and EIS techniques, while surface morphology was analyzed using SEM and AFM. The potentiodynamic polarization results revealed that cactus mucilage acts as a mixed-type inhibitor, with inhibition efficiency increasing from 78.6% at 100 mg L-1 to 94.5% at 600 mg L-1. The EIS measurements showed a significant increase in charge transfer resistance from 0.56 k? cm-2 in the uninhibited solution to 8.26 k? cm-2 with 600 mg L-1 cactus mucilage. The adsorption of cactus mucilage on the copper surface followed the Langmuir isotherm model, with a strong adsorption equilibrium constant of 23.6 × 103 M. Compared to other green inhibitors, cactus mucilage exhibited superior inhibition efficiency and sustainability advantages, making it a promising eco-friendly alternative for copper corrosion protection.

Predictive Modeling and Adsorption Behavior, Kinetics, and Thermodynamic Studies of <i>Anthocleista grandiflora </i>Leaf Extract for Corrosion Inhibition of Carbon Steel in Seawater

This study investigates the corrosion inhibition performance of Anthocleista grandiflora leaf (AGL) extract on carbon steel in seawater, considering the effects of temperature, immersion time, and inhibitor concentration. Predictive modeling, adsorption behavior, and the kinetics and thermodynamics of the inhibition process were examined. The weight loss technique,characterization techniques combined with response surface methodology (RSM), revealed that the AGL extract follows the Langmuir adsorption model, exhibiting physical adsorption with ΔG values between −16.24 to −15.49kJ/mol, indicating spontaneous and endothermic inhibition. The thermodynamic parameters entropy (−198.87 to −52.58 J/mol), enthalpy (20.42 to 53.42 kJ/mol), and activation energy (13.68 to 56.32 kJ/mol further support this. The corrosion reaction follows first-order kinetics, with the half-life decreasing as the rate constant and extract concentration increase.The SEM images revealed that the AGL extract formed a protective surface layer on the mild steel, effectively preventing pitting. This protective effect became more pronounced as the concentration of the extract increased. RSM optimization identified optimal conditions for maximum inhibition efficiency (98.70%) and corrosion rate (0.058 mm/y) at 800 ppm, 303 K, and 45 days, with a prediction accuracy of 95%, making it suitable for application in the oil and gas industry.

Synthesis, Characterization and Theoretical Calculations of a Novel Organic Corrosion Inhibitor for Mild Steel

Abstract Q235 is a carbon structural steel sheet that is widely employed in the construction and engineering sectors due to its cost-effectiveness and durability. Here, A novel organic corrosion inhibitor for Q235 sheet based on furan-thiadiazole (5-amino-2-furyl-1, 3, 4-thiadiazole, AFTZ) has been designed, successfully synthesized and characterized in this work. Results of experimental data and theoretical calculations indicated that AFTZ has an excellent corrosion inhibition property for Q235 sheet in 1.0 mol/L H2SO4. The highest efficiency of corrosion inhibitor tested by weight loss experiment can reach 91.17% and electrochemical experiment was up to 95.85% when AFTZ increased to 2 mg/mL in H2SO4 solution. The morphological characteristics of Q235 sheets with or without corrosion inhibitor showed that the target inhibitor has good corrosion inhibition performance. Quantum computation using the DFT method of guassian09 software and FT-IR date attribute the excellent corrosion inhibition to the film-forming nature of AFTZ.

Insight into the Corrosion Inhibition Performance of Pistia stratiotes Leaf Extract as a Novel Eco-Friendly Corrosion Inhibitor for Mild Steel in 1 M HCl Solution

In this research, the Pistia stratiotes leaf (PSL) extract was evaluated as a green corrosion inhibitor for the corrosion of mild steel in 1 M HCl using electrochemical measurements and surface characterization. Electrochemical impedance spectroscopy (EIS) spectra showed that the inhibitory activity of the phytochemical compounds enhanced with increasing concentration up to 400 ppm, which was reflected in the increase in the charge transfer resistance and double-layer capacitance. Regarding the effect of immersion time, EIS results indicated that the persistence of the PSL extract was between 4 h and 8 h of exposure time. From polarization curve (PCC) results, the best performance of the corrosion inhibitor was achieved at 400 ppm with an inhibition efficiency of 93.7%. The PSL extract acted as a mixed-type corrosion inhibitor. The adsorption of the phytomolecules on the metal surface obeyed the Langmuir isotherm through a mixed mechanism (physical and chemical interactions) dominated by physisorption. Scanning electron microscopy (SEM) examinations and energy-dispersive X-ray spectroscopy (EDS) elemental analysis of the corroded samples confirmed the anticorrosive protection of the PSL extract. Chemical characterization of the PSL extract by GC-MS revealed the presence of phytol, steroids, and aromatic and long-chain unsaturated fatty acid esters, in order of abundance. Chemical quantum calculations by DFT allowed for determining that the phthalic acid, di(2-propylpentyl) ester compound has the most significant potential to act as the main active component in corrosion inhibition activity.

Water Quality Analysis of a 300 Mvar Large-Scale Dual Internal Water Cooling Synchronous Condenser External Cooling System and Exploration of Optimal Water Treatment Agent Dosage at Different Temperatures

The external cooling water system of a 300 Mvar dual internal water cooling synchronous condenser at a certain ultra-high voltage converter station continued to exhibit significant scaling and corrosion, even with regular addition of scale and corrosion inhibitors. To solve this problem, the external cooling water of the synchronous condenser was sampled and tested periodically, with the main test items including conductivity, pH value, turbidity, hardness, alkalinity, and other water quality parameters directly related to corrosion and scaling. The trends of these parameters over time were also analyzed. The results showed that as the operation time increased, the cooling water became concentrated during multiple circulation cycles, and the various dissolved or suspended substances underwent a certain degree of enrichment. However, the addition of scale and corrosion inhibitors did not dynamically adjust according to the changes in water quality, and there was always an excessive dosage. Thus, using the external cooling water as the experimental sample, static scale inhibition tests and rotating coupon corrosion tests were conducted to evaluate the scale and corrosion inhibition performance of the commercial AS-582 scale and corrosion inhibitor used at this ultra-high voltage converter station under different conditions. Considering the more obvious corrosive tendency of this water sample, the focus was on testing its corrosion inhibition performance. When the dosage was 600 ppm, the scale inhibition effect was optimal, with an inhibition rate of 92.15%. The corrosion inhibition effect of this scale and the corrosion inhibitor were significantly related to water temperature. At 25 °C, when the dosage was 500 ppm, the corrosion inhibition effect was optimal, with an inhibition rate of 86.79%. However, when the temperature increased to 40 °C, the corrosion inhibition effect under each dosage was significantly worse, unable to meet the requirements, and the use of other corrosion inhibitors in combination was necessary. This work will provide a reference for the scientific use of scale and corrosion inhibitors.

A retarded foam acid fluid system for low-temperature dolomite geothermal reservoir stimulation and its action mechanisms

Acidizing improves geothermal reservoir productivity by dissolving rocks to increase formation permeability, which is achieved by injecting acid fluids into reservoir formations. However, conventional acid fluids either can not achieve effective acidizing or cause geothermal reservoir damages. Foam acid fluids, which have been applied for oil-gas reservoir stimulation, can realize effective acidizing by retarding acid-rock reactions, and can protect reservoirs. Here, a foam acid fluid system is proposed, aiming at achieving efficient acidizing and reservoir protection in low-temperature dolomite geothermal reservoirs. Formic acid (FA) and acetic acid (HAc) are used to replace a portion of hydrochloride (HCl) acid. Alkyl glycine surfactant AGS-12 is added for foaming, while xanthan gum and nano silica particles are used to stabilize foams. Corrosion inhibitor and ferric ion stabilizer are added to inhibit acid corrosion of steel and ferric ion precipitations. The acidizing effect was evaluated through foam stability, dissolution performance, corrosion inhibition performance, and compatibility. Microscopic observation, field emission scanning electron microscope, and numerical simulation were applied to reveal the mechanisms of temporal evolution of foams and acid dissolution behaviors. Results show that the foam acid fluid with 5 wt% FA, 5 wt% HAc and 10 wt% HCl acid has the best foam stability and retardation effect. Compared to non-foam acid fluid, the decrease degree of the cuttings mass change rate in foam acid fluids exceeds 50 %, and foaming primarily retards acid-rock reactions. Simulation results is consistent with the experiment results, demonstrating that the cuttings dissolve less in FA and HAc. Calcium (Ca) content on the cuttings surfaces after acid-rock reactions in foam acid fluids with FA and HAc is less than that after acid-rock reactions in foam acid fluid with sole HCl acid, indicating that FA and HAc inhibit Ca-bearing mineral precipitations, as formate and acetate ions can chelate with Ca2+. The replacement of HCl acid by FA and HAc contributes to a low corrosivity and good compatibility of the foam acid fluids due to a reduced hydrogen ions resulted from partial dissociation of weak acids. This study shows the feasibility of foam acid fluids during geothermal reservoir stimulation with eliminated reservoir damages.

Ensemble Stacking of Machine Learning Approach for Predicting Corrosion Inhibitor Performance of Pyridazine Compounds

Corrosion is a major challenge affecting various industrial sectors, leading to increased operational costs and decreased equipment efficiency. The use of organic corrosion inhibitors is one of the promising solutions. This study applies an ensemble algorithm with a stacking method to estimate pyridazine-derived compounds corrosion inhibition efficiency. This study utilized various molecular characteristics of pyridazine compounds as inputs to predict inhibition efficiency values. After evaluating several boosting models, the stacking technique was chosen as it showed the best results. Stacking Model 6, which combines XGB, LGBM, and CatBoost as the base model with Random Forest as the meta-model, produced the most accurate prediction with an RMSE of 0.055. These findings indicate that machine learning approaches can effectively and efficiently predict corrosion inhibitor performance. This method offers a faster and more economical alternative to conventional experimental methods.

Impact of N-Decyl-Nicotineamide Bromide on Copper Corrosion Inhibition in Acidic Sulphate containing Environment: electrochemical and Piezoelectrochemical Insights

This work investigates the inhibition effect and adsorption properties of a new tailor-made synthesized model molecule of ionic liquids, namely N-decyl nicotinamide bromide [C10Nic]Br in an acidic 0.1 M Na2SO4 solution (pH = 2.7) against the corrosion of copper. Electrochemical methods (ac electrochemical impedance spectroscopy and dc potentiodynamic polarization), and piezoelectric method (quartz crystal microbalance with impedance analysis (EQCM-I) were applied to study the corrosion protection performance of the inhibitor. Electrochemical measurements have indicated favorable corrosion inhibition performance of [C10Nic]Br. The corrosion inhibition efficiency increases with the increase of inhibitor concentration, at a [C10Nic]Br concentration of 10-3 M the efficiency reaches 93%. The inhibitor adsorption slightly differed from the ideal Langmuir adsorption isotherm. [C10Nic]Br can be considered to be a mixed-type inhibitor. The inhibition efficiency was found to be time-dependent. In the presence of the highest 10-3 M inhibitor concentration the formation of the maximum protective effect of the inhibitor layer takes several hours, the maximum value of polarization resistance was 8.5 kΩ.cm2 after 5 hours. The copper dissolution and the inhibitor adsorption were also monitored by real-time changes in mass and viscoelasticity determined by QCM-I. It was obtained that the inhibitor adsorption on the copper surface leads to a decrease in copper dissolution and an increase in viscoelasticity. The layer on the copper surface becomes softer due to the complex between the inhibitor and the corrosion products on the surface.

Carbon dot aggregates: a new strategy to promote corrosion inhibition performance of carbon dots

The corrosion of metal not only produces serious economic losses and environmental pollution but also threatens equipment safety. Carbon dots (CDs) exhibit outstanding inhibition properties to availably retard the corrosion of metal. However, the present CDs-based corrosion inhibitors still fail to fully exert the environmentally friendly and low-cost merits of CDs. To address this issue, CD aggregates (CDAs) prepared by low-cost and eco-friendly CDs are developed as novel corrosion inhibitors for the first time, and their corrosion inhibition mechanism is disclosed. Specifically, CDAs with excellent long-term dispersion stability are synthesized by solvothermal treatment of CDs formed by citric acid and urea. CDAs at only 200 mg/L provide a corrosion inhibition effect of 90.38% for Q235 carbon steel in 1 mol/L HCl solution, approximately 1.53 times higher than that of CDs (59.21%). Moreover, the corrosion inhibition mechanism of CDAs is proposed through the analysis of adsorption isotherm, examination of corrosion morphologies, and theoretical calculations. That is, CDAs physically and chemically adsorb on the carbon steel surface, mainly hindering its anodic reaction, thus retarding the corrosion of carbon steel. This research firstly verifies the corrosion inhibition potential of green and low-cost CDAs and provides a novel strategy to promote the corrosion inhibition performance of CDs, promoting the progress of aggregate-based corrosion inhibitors.

Corrosion inhibition performance of protein derived carbon quantum dots as corrosion inhibitors on low carbon steel in sulfuric acid solution

Protein derived carbon quantum dots (PCQDs) were successfully fabricated via a hydrothermal method with shrimp meat as the precursor. Subsequently, their corrosion-inhibiting performance on mild steel (L-steel) in a 0.5 mol/L H2SO4 solution was evaluated. Electrochemical impedance spectroscopy (EIS) tests demonstrated that at a concentration of 250 mg/L, the corrosion inhibition efficiency of PCQDs exceeded 90 %. Potentiodynamic polarization (PDP) tests indicated that when the concentration of PCQDs reached 500 mg/L, the corrosion inhibition efficiency was as high as 97.45 %. Comprehensive characterizations of the PCQDs, including X-ray diffraction (XRD), transmission electron microscopy (TEM), Fourier transform infrared spectroscopy (FTIR), and ultraviolet–visible spectroscopy (UV–Vis), verified the existence of functional groups such as carboxyl, hydroxyl, and aromatic rings within the PCQDs. These groups are conducive to forming a strong adsorption force on the surface of L-steel and creating a protective layer. Surface morphology analyses carried out by scanning electron microscopy (SEM) and atomic force microscopy (AFM) revealed that the surface of L-steel treated with PCQDs was significantly smoother in comparison to untreated samples exposed to acidic conditions. Adsorption studies disclosed a mixed physical and chemical adsorption behavior, and theoretical calculations showed that the N and S atoms in PCQDs preferentially adsorb in a parallel direction. The addition of PCQDs led to a reduction in the diffusion coefficient, indicating that the diffusion of corrosive ions was effectively hindered. The distribution function of PCQDs was 3.48 Å, which suggested that the chemisorption mechanism played a dominant role in the inhibition process.

Performance and mechanism of triethanolamine-triisopropanolamine corrosion inhibitor to deterioration of reinforced concrete under the coupling effect of freeze-thaw cycles and chloride attack

The purpose of this study is to propose an efficient and economical organic triethanolamine-triisopropanolamine corrosion inhibitor (OTTCI) to reduce the corrosion of steel in reinforced concrete. The influence of OTTCI on corrosion of steel in reinforced concrete under the coupling effect of freeze-thaw cycles and chloride attack (FTCs-CA) were characterized by electrochemical impedance spectroscopy (EIS), dynamic electrode potential (PDP), mechanical properties (mass loss rate (M), compressive strength (fn) and relative dynamic elastic modulus value (Pi)), capillary water absorption (CWA), bubble spacing coefficient (BSC) and scanning electron microscope (SEM). The inhibition mechanism of OTTCI was also analyzed and summarized. The results displayed that the dosage of OTTCI delayed the degradation of reinforced concrete under FTCs-CA. After 150 cycles, the M value of specimens with 1.0 % OTTCI reduced by 66.31 % compared to that of specimens without OTTCI, the Pi value increased by 51.9 %, and the polarization resistance and corrosion inhibition efficiency reached 2744.19 Ω cm2 and 92.88 %, respectively. In addition, OTTCI significantly reduced the CWA value and porosity. After 150 cycles, the CWA and porosity with 1.0 % OTTCI decreased by 60.1 % and 54.54 % respectively. The capillary water absorption coefficient increased linearly with the increase of FTCs-CA. SEM tests illustrated that OTTCI inhibited the development of internal cracks and macropores in concrete and promoted the formation of hydrated calcium silicate gels and calcite. The application of this study not only provides a new method to alleviate the deterioration of reinforced concrete, but also offers theoretical and technical support for further investigate on the deterioration characteristics of reinforced concrete in harsh environments.

Synthesis, characterization and performance of ecofriendly epoxy resin as a highly efficient corrosion inhibition for mild steel in 1m HCl solution

In this study, a novel epoxy resin called tetraglycidyl ether of methyl-α-D-mannopyranoside (TGEMM) was synthesized and investigated for its potential used as a corrosion inhibitor for mild steel in a 1.0 M hydrochloric acid (HCl) solution. The main goal was to evaluate the corrosion inhibition properties of TGEMM using various techniques. The methods used in this research included potentiodynamic polarization, electrochemical impedance spectroscopy (EIS), temperature effect, scanning electron microscopy, energy dispersive X-ray spectroscopy, atomic force microscopy and contact angle measurement. These techniques were chosen to comprehensively assess the corrosion inhibition performance of TGEMM on MS. In this context, the structure of the newly synthesized TGEMM epoxy resin was identified and confirmed using Fourier transform infrared spectroscopy (FTIR) and nuclear magnetic resonance (NMR). The results obtained from the experiments demonstrated that, at a lower concentration of 10−3 M, TGEMM demonstrated a high inhibitory efficacy of 91.49%, assessed via electrochemical impedance spectroscopy (EIS), and 93.84%, measured via potentiodynamic polarization (PDP), in a 1.0 M hydrochloric acid solution. The PDP data indicated that the TGEMM epoxy resin acted as an anodic inhibitor in the acidic environment. In addition to gain insights into the interaction mechanism and adsorption mode, DFT and MD simulations were conducted, revealing valuable information about the interaction of TGEMM with the mild steel surface.

Electrochemical, surface, and theoretical investigations of palm kernel shell extract as an effective inhibitor for carbon-steel corrosion in 1M HCl solution.

Herein, we employed palm kernel shell extract (PKSE) as an eco-friendly inhibitor for carbon steel in acidic-induced corrosion. The corrosion inhibition of PKSE on carbon steel in 1M HCI solution was investigated by electrochemical impedance spectroscopy, weight loss, and potentiodynamic polarization measurements. The surface was characterized by scanning electron microscopy equipped with energy-dispersive X-ray spectroscopy. Moreover, the elastic modulus and hardness tests were conducted. Weight loss measurements revealed that the optimum concentration of inhibitors is 500ppm with 95.3% inhibition efficiency in 1M HCl solution. Electrochemical results showed that the inhibitor could exhibit excellent corrosion inhibition performance and displayed mixed-type inhibition. The electrochemical impedance spectroscopy analysis shows that the inhibition performance increases by increasing the concentration of PKSE. The surface studies ensure the PKSE effectiveness in carbon steel surface damage reduction. Also, the adsorption of PKSE molecules on the carbon steel surface occurs according to the Langmuir isotherm model. The primary goal of this investigation was the utilization of palm kernel shell extract as corrosion inhibitor for 1018 low carbon steel in 1M HCl solution, which highlights its novelty. The present results will be helpful to uncover the versatile importance of palm kernel shell compounds in the corrosion inhibition process.

Investigating the synergistic effect of fish waste extract and KI on the corrosion inhibition of carbon steel in sulfuric acid solution

Biowaste has become a serious problem that can lead to serious environmental pollution and waste of resources if not handled properly. Waste materials are often high in proteins, which are easily extracted and hydrolyzed to provide an adequate quantity of amino acids. This indicates that biowastes can be used as green and efficient corrosion inhibitors (CIs). This work aimed to prepare fish waste extract (FWE) by acid hydrolysis with alkaline leaching using fish waste as the raw material. The results of the characterization analysis identified the presence of 17 amino acids, with Leucine, Phenylalanine, Methionine, and Alanine being the most abundant. FWE was then tested as a corrosion inhibitor (CI) for carbon steel in 0.5 mol/L H2SO4. Further, the effect of KI on the corrosion inhibition performance of FWE for carbon steel in 0.5 mol/L H2SO4 was systematically investigated by the weight loss method, electrochemical method, and surface analysis. The maximum corrosion inhibition efficiencies were 88.7 % and 63.9 % for the FWE and KI alone, and 97.10 % for the combination of FWE and KI. The synergistic coefficient study confirmed that the synergistic coefficients of the FWE and KI exceeded 1 across all concentration conditions, indicating a synergistic effect between them. The surface analysis results showed that the deterioration of carbon steel after adding the compounded CI was mild, and pitting and crevice corrosion was not observed. Theoretical calculations revealed the active reaction sites of four major amino acid molecules via quantum chemical and molecular dynamics simulations. The effect of different types of side chains and heteroatoms of amino acid molecules on their corrosion inhibition performance was elucidated to provide theoretical guidance for designing biowaste CIs.

Development and Application of a Chelating Acid for Water Injection Wells of Chang 6 Reservoir of An-Sai Oilfield

Abstract Ansai oilfield is a typical low permeability, low pressure, low yield and serious heterogeneity oilfield. Chang 6 play of Triassic YanChang Formation is a typical ultra-low permeability reservoir. The average porosity of the reservoir is 10 % ~ 14 %, and the average permeability is (0.2 ~ 4.0) × 10−3 μm2. The absolute content of clay minerals in the reservoir is relatively high, with an average content of 18.61 %. The main components are kaolinite, chlorite, illite and illite/montmorillonite interlayer. Due to the reservoir blockage caused by scaling, water sensitivity and formation particle migration in the process of water injection, high injection pressure and under injection wells is increasing dramatically. In view of the above challenges, a fit-for-purpose acid, which contains organic acids and chelating agents, was developed for injection pressure reduction and injection enhancement. It has the characteristics of strong dissolution, good retarding and corrosion inhibition performance. Corrosion rate is 0.5632 g / (m2·h) for J55 steel in 24h, and the core permeability increases by 74.57 % after acid flooding. It has been applied in field test of 3 wells in Chang 6 layer of Ansai oilfield since March 2024. The average daily injection volume increased by 37.87 %, and the validity period was more than 180 days.

Fluorine-free superhydrophobic Ni/Mn-TiO2 composite coatings on carbon steel via one-step electrodeposition for enhanced durability and corrosion resistance

The application of superhydrophobic coatings on carbon steel (CS) surface represents an effective strategy for mitigating corrosion in these materials. This study presents the preparation of superhydrophobic Ni/Mn-TiO2 composite (SNMT) coatings on CS substrates through a facile one-step electrodeposition technique. The formation mechanism of SNMT coatings was meticulously analyzed under varying conditions of nanoparticle types and concentration levels. The inclusion of TiO2 nanoparticles, with an optimal additive concentration of 1 g, facilitated the formation of numerous low surface energy, cauliflower-like microstructures on CS interface. Surprisingly, the results indicate that SNMT coatings maintained commendable superhydrophobicity even post-exposure to superficial damages such as tape peeling, sandpaper wear, and knife-scratch, as evidenced by a static contact angle (CA) exceeding 158° and a sliding angle (SA) below 2°. Furthermore, the corrosion inhibition efficacy of SNMT coatings was quantitatively assessed via dynamic potential polarization curves in a simulated seawater environment. The results demonstrated that SNMT coatings exhibited excellent corrosion inhibition performance in simulated seawater solution, with a protection efficiency (PE) reaching 96.5%. In conclusion, superhydrophobic surfaces can effectively inhibit the penetration of corrosive liquids. The durability and robustness of such superhydrophobic surfaces advocate for their potential widespread application in enhancing the longevity and reliability of CS in corrosive environments.

Corrosion Inhibition Performances of Amino Acids Corrosion Inhibitors on Carbon Steel in Sulphuric Acid Medium

Abstract The amino acids have great potential in inhibiting metal corrosion. The corrosion inhibition performances of amino acids corrosion inhibitors on A3 carbon steel in sulphuric acid medium were investigated by weight loss method. The corrosion inhibition performances of the alanine, glycine, aspartate, arginine and methionine increase gradually with the dosage of amino acid corrosion inhibitor increase gradually. The five composite corrosion inhibitors were prepared by compound of the five amino acid and potassium iodide respectively to improve the corrosion inhibition performances of amino acids. The corrosion inhibition rate of the five composite corrosion inhibitors is about 20% higher than the amino acid corrosion inhibitors respectively. The amino acid and potassium iodide composite corrosion inhibitors have good protective effects on A3 carbon steel at 30-45°C. The amino acid and potassium iodide composite corrosion inhibitors used for sulfuric acid medium have good protective effects on A3 carbon steel.

Synthesis and evaluation of an environmentally friendly phosphorus-free and nitrogen-free polymer as a scale and corrosion inhibitor

Polyepoxysuccinic acid (PESA) was modified by glycidyl (Gly) to obtain a phosphate-free and nitrogen-free polymer (Gly-PESA), and its scale and corrosion inhibition properties were studied.The effects of Gly-PESA concentration, calcium ion concentration and temperature to scale inhibition performance were studied by static scale inhibition method. The corrosion inhibition performance of Gly-PESA was studied by static weight-loss method. The morphology and structure of calcium scale and steel surface were characterized by spectroscopic and microscopic methods. The scale inhibition efficiency of Gly-PESA for CaCO3 and CaSO4 was 98.06% and 92.6%, respectively. Under the same experimental conditions, the scale inhibition effect of Gly-PESA was obviously better than that of PESA. Gly-PESA could effectively inhibit the growth of CaCO3 and CaSO4 crystals and cause their crystal lattice distortion or crystal dispersion. The corrosion inhibition efficiency of Gly-PESA for carbon steel was 78.17%. The adsorption of Gly-PESA on the surface of the steel test piece followed Langmuir adsorption isotherm, and formed a protective film, which increased the corrosion resistance of the steel test piece, thus effectively protecting the steel test piece. Therefore, Gly-PESA was a green scale and corrosion inhibitor, which solved the problem of environmental pollution.

Extract of Silybum marianum (L.) Gaertn Leaves as a Novel Green Corrosion Inhibitor for Carbon Steel in Acidic Solution

In this work, leaves of Silybum marianum (L.) Gaertn were extracted by a one-step extraction method using ethanol as a solvent, and the Silybum marianum (L.) Gaertn extract (SMGE) was firstly employed as a green corrosion inhibitor for carbon steel in 0.5 mol/L H2SO4. The corrosion inhibition performance was studied using weight loss and electrochemical methods, and the anti-corrosion mechanism of SMGE is further analyzed through some surface characterizations and theoretical calculations. The results indicate that SMGE can act as a mixed-type corrosion inhibitor and possess superior corrosion inhibition performance for carbon steel in H2SO4 solution, and the optimum corrosion inhibition efficiency reached 93.06% at 800 ppm SMGE combined with 60 ppm KI. The corrosion inhibition efficiency increased with the rising inhibitor concentration. Surface characterizations illustrated that the inhibitor could physico-chemically adsorb on a metal surface, forming a hydrophobic, protective film.