Inhibition Of Acid Corrosion Research Articles

Glucamines as green alternatives to conventional amino alcohols in metalworking fluids

AbstractAmino alcohols like triethanolamine (TEA), 2‐amino‐2‐methylpropanol (AMP), or 1‐aminopropan‐2‐ol (MIPA) are common ingredients in industrial metalworking fluids. They are used in large quantities as alkaline additives for the neutralization of acidic corrosion inhibitors and are typical industrial products from the oil‐based value chain. The criteria for the selection of these additives have changed in the last decades and are nowadays not only performance‐driven but influenced by ecological considerations, toxicity, and regulatory standards. In this study, we evaluate the sugar derivative N,N‐diethylglucamine (DEGA) for use as a functional, nonvolatile, chemically stable, and cheap alkaline additive for common acidic corrosion inhibitors. Electrochemical analyses confirm anticorrosive properties of DEGA comparable to the gold standard TEA for iron and steel in an aqueous environment at a slightly alkaline pH. In addition, DEGA leads to extremely low levels of Co, Ni, and Cu leaching and can thus also serve as a nonvolatile substitute for currently used low‐leaching additives such as AMP and MIPA. The diethylamino‐motif is a sweet spot among different glucamine derivatives tested because it combines easy synthetic accessibility with good water solubility and low‐leaching properties. Besides this, DEGA can be prepared in one step from glucose and diethylamine, both derived from renewable resources.

Use of orange peel extract as an inhibitor of stainless steel corrosion during acid washing in a multistage flash desalination plant

Environmentally friendly and cost-effective inhibitors based on orange peel extract (OPE) have been developed for potential applications in ejector tubes of a multistage desalination plant during the acid cleaning process. After conducting tests under both static and hydrodynamic circumstances, it was determined that the inhibitor formulation was effective against corrosion of stainless steel (SS) in 1 M HCl solution at 30 °C under the conditions tested. Electrochemical methods were used along with electron microscopy to collect information on the corrosion inhibition efficiency of the extract. Experiments were conducted for 1, 2, 3, 4, 6, 12, and 24 h, and the performance of OPE was compared to that of a commercial acid corrosion inhibitor to determine which performed better. The results revealed that OPE demonstrated outstanding corrosion inhibition performance compared to the commercial acid corrosion inhibitor. With remarkable inhibition efficacy for up to 24 h under both static and dynamic settings, 0.4% of OPE displayed typical mixed-type corrosion inhibitor behavior in the tested environment. All of the procedures that were used produced results that were in good agreement. Due to the synergistic action between the two compounds, the corrosion inhibition of OPE on SS was improved in 1 M HCl in the presence of iodide ions. In the absence of KI, OPE was found to inhibit SS corrosion at a concentration-dependent rate, with the concentration of OPE being the most significant factor. A study of the adsorption of OPE onto a SS surface revealed that the Langmuir adsorption isotherm controls the process. Based on the quantity of free energy of adsorption observed, it was determined that there is physical contact between the OPE and the surface of SS in this experiment. It was possible to identify the most effective phytochemicals for corrosion inhibition based on the findings of quantum chemical calculations, which were subsequently evaluated in the laboratory.Graphical abstract

Advanced once-through flow cell methodology for evaluation of a new staged inhibition concept to mitigate corrosion of carbon steel in high-strength hydrochloric acid flow

A new staged acid corrosion inhibition (ACI) concept, utilising polymerisable ACIs, has been developed to minimise the corrosion of coiled tubing and wellbore casing materials during matrix acidizing operations. The concept has been evaluated using a customised once-through flow cell and 4 molar hydrochloric acid at 80 °C. A high quality, protective inhibitor film is established using an elevated ACI concentration during the test period 0–1 h (Stage 1), followed by a significantly reduced ACI concentration during the period 1–4 h (Stage 2). This approach is able to maintain good film persistency and acceptably low corrosion rates.

Effect of cation type on corrosion of steel treated by DNA corrosion inhibitor in simulated concrete pore solution

The purpose of this study is to evaluate the influence of cation types on the rust resistance performance of new nucleic acid corrosion inhibitors in simulated concrete pore solution. Four common chlorinated ice salts (sodium chloride (NaCl), potassium choride (KCl), calcium chloride (CaCl2) and magnesium chloride (MgCl2)) were selected to study the corrosion behaviour of chloride ions by linear polarisation resistance method, electrochemical impedance spectroscopy and X-ray photoelectron spectroscopy. The results show that the cationic type will affect the thickness of the passivated film on the steel surface and the compactness of the passivated film formed by iron oxide and nucleic acid rust inhibitor. The type of cations affects the critical chloride concentration of nucleic acid inhibitor, following Na+ ≈ K+ > Ca2+ > Mg2+.

Synthesis and evaluation of 1-butyl-3-methylimidazolium chloride based ionic liquid for acid corrosion inhibition of aluminum alloy: Empirical, DFT/MD-simulation and RSM modeling

The present research explores the synthesis of imidazolium based ionic liquid (IL) 1-butyl-3-methylimidazolium chloride ([BMIM][Cl]) and its application for the protection of aluminum alloy (AA) in 1 M H2SO4 electrolyte using gravimetric, potentiodynamic polarization (PDP), electrochemical impedance spectroscopy (EIS), response surface methodology (RSM), density functional theory (DFT) and MD-simulation respectively. The studied (IL) showed appreciable inhibition efficiencies of 84.21 % for gravimetric, 90 % for PDP and 87.10 % for the EIS at 0.80 g/L inhibitor concentration and 313 K, respectively. The results of EIS and PDP reveal the corrosion inhibition process is charge transfer controlled, and the studied IL acts as a mixed type inhibitor. The optimization result via RSM model gave an optimum prediction of 84.21 % at 0.8 g/L inhibitor concentration at 313 K. Adsorption of [BMIM][Cl] on the aluminum surface obeyed the Frumkin adsorption isotherm. The scanning electron microscope (SEM) and atomic force microscopy (AFM) revealed the formation of protective film of the inhibitor on the aluminum surface. Theoretical modeling were used to correlate the experimental results. The best fit of the theoretical models were functions of molecular structure and fractions of electron transferred from the inhibitor to the aluminum surface.

Formamidine-Based Thiuram Disulfides as Efficient Inhibitors of Acid Corrosion of Mild Steel: Electrochemical, Surface, and Density Functional Theory/Monte Carlo Simulation Studies.

Electrochemical, surface, and density functional theory (DFT)/Monte Carlo (MC) simulation studies were used in investigating the characteristics of N,N′-(disulfanne-1,2-dicarbonothioyl)bis(N,N′-bis(2,6-dimethylphenyl)formimidamide) (DS1), N,N′-(disulfanne-1,2-dicarbonothioyl)bis(N,N′-bis(2,6-diisopropylphenyl)formimidamide) (DS2), N,N′-(disulfanne-1,2-dicarbonothioyl)bis(N,N′-dimesitylformimidamide) (DS3), and N,N′-(disulfanne-1,2-dicarbonothioyl)bis(N,N′-bis(2,6-dichlorophenyl)formimidamide) (DS4) as inhibitors of acid corrosion of mild steel. The inhibitors were found to effectively reduce the rates of steel dissolution at the anode as well as cathodic hydrogen evolution. The order of inhibition efficiencies of studied compounds is DS1 (PDP/LPR/EIS: 98.60/97.98/96.94%) > DS2 (PDP/LPR/EIS: 98.36/96.86/96.90%) > DS3 (PDP/LPR/EIS: 94.66/87.44/94.30%) > DS4 (PDP/LPR/EIS: 83.57/77.02/75.17%) at 1.00 mM, and the overall efficiencies appeared to depend on the molecular and electronic structures of the compounds. The compounds offered high resistance to charge transfer across the electrode/electrolyte system by forming adsorbed film whose resistance increased with an increase in concentration. Findings suggested that the adsorption process involved combined chemisorption and physisorption. DFT calculations and MC simulations provided theoretical justifications for the experimental results.

Cupressus arizonica fruit essential oil: A novel green inhibitor for acid corrosion of carbon steel

Natural-based corrosion inhibitors have gained great research interest thanks to their low cost and higher performance. The Cupressus arizonica fruit essential oil (CAFEO) has a higher extraction yield than leaves; however, it has less antibacterial and antifungal activities. The three main components in the CAFEO were α-pinene (51.07%), myrcene (17.92%), and limonene (9.66%). Essential oils with a higher percentage of α-pinene were found to have outstanding corrosion inhibition properties. Therefore, herein, the CAFEO was investigated as a green corrosion inhibitor for carbon steel (CS) in 1.0 mol/L HCl using electrochemical, i.e., potentiodynamic polarization (PDP) and electrochemical impedance spectroscopy (EIS), and scanning electron microscope (SEM) techniques. The experimental results revealed that CAFEO successfully inhibited the carbon steel corrosion in 1.0 mol/L HCl solution. Results from PDP indicated that the inhibitor had a mixed-type effect with a predominance cathodic character. EIS data showed that the charge transfer resistance of the CS electrode increased from 20.9 Ω cm2 in blank solution to 294.5 Ω cm2 in HCl solution inhibited with 0.5 g/L of CAFEO at 298 K, leading to a significant decrease in the double layer capacitance values and an inhibition efficiency (η%) of 93%. The high temperatures showed a negative effect on the corrosion inhibition efficiency of the tested inhibitor. At 323 K, the η% of CAFEO decreased to 77%. Besides, SEM images showed that the inhibitor formed a protective barrier against acid attack, preventing carbon steel from corrosion. Theoretical calculations by Density Functional Theory (DFT) were performed to investigate the reactivity of the three main components of CAFEO.

Computational, kinetic, and electrochemical studies of polyaniline functionalized ZnO and ZnO-SiO2 nanoparticles as corrosion protection films on carbon steel in acidic sodium chloride solutions

Two novel nanocomposites based on polyaniline functionalized ZnO and ZnO-SiO2 nanoparticles (ZnO@PANi and ZnSiO@PANi) were synthesized, characterized, and evaluated as protective films for steel pipelines in the pickling process at 25–55 °C. The prepared nanocomposites were described using different spectroscopic characterization methods including UV–vis, FTIR, DLS, XPS methods, and other physicochemical techniques including XRD, FESEM, and HR-TEM. The novelty of these films is in the fact that the ZnO and ZnO-SiO2 nanoparticles are functionalized by polyaniline which is electrochemically stable in acidic solution and has high conductivity. Electrochemical systems such as open circuit potentials (OCP), electrochemical impedance spectroscopy (EIS), and potentiodynamic polarization (PDP) were utilized to attain the kinetics and mechanistic findings of the corrosion protection route. The outcomes indicate that the two fabricated ZnO@PANi and ZnSiO@PANi are efficient acidic corrosion inhibitors. The protection performance of ZnSiO@PANi (98.6%) was more pronounced at a dose (150 mg/L) than ZnO@PANi (92.3%) and individual PANi (83.4%) as achieved from PDP findings. The effect of temperature and flowing conditions reinforces further the performance of both nanocomposites. Surface characterization using FESEM/EDS delivered more indication for the steel surface protection with the ZnO@PANi and ZnSiO@PANi nanocomposites. Molecular modeling using DFT calculations and MC simulations supported the experimental findings. The binding energies of the compounds and Fe interface follow the order of ZnO@PANi > ZnSiO@PANi, which is in good agreement with the empirical results. An important suggestion of these results is the probability of substituting traditional toxic small molecules with cost-effective and non-toxic polymeric nanocomposites as protective films for use in the oil and gas industry.

Synthesis and characterization of novel ionic liquids based on imidazolium for acid corrosion inhibition of aluminum: Experimental, spectral, and computational study

Three newly ionic liquids namely, 1-bnzyl-2-methyl-3-octyl-1H-imidazol-3-ium bromide, 1-bnzyl-3-decyl-2-methyl-1H-imidazol-3-ium bromide, and 1-bnzyl-3-dodecyl-2-methyl-1H-imidazol-3-ium bromide are synthesized and their chemical structures characterized via different spectra techniques (FT-IR, elemental analysis,and 1H NMR). The corrosion inhibition of newly ionic liquids was evaluated on aluminum alloy in 1 M HCl at varied exposure temperatures (298–318 K) and varied concentrations via various experimental and theoretical methods for example mass loss, electrochemical, spectral, and computational calculations. The results illustrate that these types of ionic liquids inhibit corrosion of aluminum in acid solution with maximum inhibition efficiency was reached 83.2 % at 298 K. The inhibition efficiency increases with the addition of zinc sulfate which has a synergistic impact which was reached to 92.7%. Also, the concentration of ionic liquids and the kind of cation have an impact on the obtained results. The existence of these inhibitors in the acidic solution improves the charge transfer resistance and lessens the double-layer capacitance. The Langmuir adsorption isotherm governs the adsorption of these inhibitors' molecules on the aluminum alloy surface, and they behave as mixed-type inhibitors. The outputs reveal that the computational calculations match the experimental data rather well.

Studying the effect of two isomer forms thiazole and thiadiazine on the inhibition of acidic chloride-induced steel corrosion: Empirical and Computer simulation explorations

Two isomeric forms thiadiazines (AZIN) and thiazoles (AZOL) are produced through a simple reaction of monohydrazone with α-haloketohydrazonoyl derivatives in the alkaline medium. The prepared materials were characterized through spectral information. The corrosion inhibition performance of AZIN and AZOL for the C-steel corrosion in a 15% hydrochloric acid solution was evaluated via Open circuit potential (EOCP) vs. time, electrochemical impedance spectroscopy (EIS), and potentiodynamic polarization (PDP) techniques. The inhibition efficiencies of AZIN and AZOL at an optimum concentration (2.0 × 10-3 M) are 96.4% and 98.3% at 50 °C, respectively. The assessed values of the standard adsorption free energy (ΔGads0) revealed the typical behavior of physisorption and chemisorption of AZIN and AZOL on C-steel and followed the Langmuir isotherm model. Surface morphology studies by FTIR and FESEM analyses confirmed the adsorption of the AZIN and AZOL molecules on the C-steel interface. Density functional theory (DFT) calculations and Monte Carlo (MC) simulations exhibited that the efficiency of the AZIN and AZOL associates well with their structures and this protection was due to their adsorption on metal surfaces.

Ингибиторы кислотной коррозии на основе амидов олеиновой кислоты

The destruction of petrochemical production equipment resulting from acid corrosion is one of the main problems faced by the oil refining industry. A promising way to protect structural steel from acid corro-sion is the use of corrosion inhibitors. The paper shows the possibility of using oleic acid amides, contain-ing a sulfogroup, as well as their salts as acid corrosion inhibitors. The studied compounds were obtained by three successive syntheses, optimal conditions for the quantitative production of target products were selected. The physicochemical characteristics of the obtained compounds were determined.

Synthesis and characterization of nano-SiO2@octadecylbisimidazoline quaternary ammonium salt used as acidizing corrosion inhibitor

AbstractAiming at the current situation that the existing acidizing corrosion inhibitors are difficult to apply in high temperature, high concentration acid, and other complex conditions, this article uses nano-SiO2as the core and preferably functional monomers to synthesize nano-SiO2@octadecylbisimidazoline quaternary ammonium salt (nano-SiO2@OBQA). Analytical methods such as nuclear magnetic resonance, infrared, and scanning electron microscopy were used for characterization. The corrosion inhibition performance of the N80 steel sheet by nano-SiO2@OBQA in 20% concentrated hydrochloric acid was studied using the high-temperature corrosion testing machine and adsorption isotherm model combined with quantum chemistry calculations to explore its mechanism of action. The results show that nano-SiO2@OBQA has good high-temperature resistance. When the temperature is 180℃ and the dosage of nano-SiO2@OBQA is 4%, the corrosion inhibition rate is 61.42 g·m−2·h−1. Studies have shown that the adsorption of nano-SiO2@OBQA on the surface of the N80 steel sheet follows the Langmuir isotherm adsorption model, which is spontaneous chemical adsorption.

One-Pot Hydrothermal Synthesized Nitrogen and Sulfur Codoped Carbon Dots for Acid Corrosion Inhibition of Q235 Steel.

N and S codoped carbon dots having good water solubility have been successfully made by a novel hydrothermal method and characterized by FTIR, XPS, and TEM. The as-synthesized CDs were carbon particles rich in polar functional groups less than 10 nm in size. Electrochemical measurements, gravimetry, and surface analysis methods were utilized to examine the inhibition characteristics and adsorption mechanism of CDs on the carbon steel in acid pickling solutions. Electrochemical measurements verified that the CDs displayed adequate protection with high inhibition efficiency of 97.8%. The long-term weight-loss experiments up to 72 h further confirmed the excellent corrosion inhibition at room temperature and 313 K. The results presented are helpful for the formulation of more effective acid pickling corrosion inhibitors.

Corrosion inhibition of steel by selected homologues of the class 3-alkyl-5-amino-1H-1,2,4-triazoles in acidic media

The use of hydrochloric acid in the treatment of the bottomhole formation zone leads to the significant corrosion of metals, as well as hydrogen and chloride stress cracking of pump compressor pipes. In order to solve this problem, corrosion inhibitors are added to a hydrochloric acid solution. This article presents the results of a study of the anticorrosive activity of a number of derivatives of the class of 3-alkyl-5-amino-1H-1,2,4-triazole under the conditions of hydrochloric acid corrosion of low-carbon steel. During the study, selected 3-alkyl-5-amino-1H-1,2,4-triazoles were synthesized. Their structure was confirmed and proved using NMR spectroscopy and HPLC/MS spectrometry. Regularities of the anticorrosive ction of the investigated compounds have been established using polarization electrochemical studies and gravimetric direct corrosion tests. Corrosion rates, inhibition coefficients and degrees of protection have been calculated for all inhibitors. The probable mechanism of the inhibitory action of the studied compounds has been substantiated using quantum chemical calculations based on the density functional theory using the Gaussian program. It was shown that the structure of the alkyl substituents has the greatest effect on the inhibitory activity of the studied compounds. The mechanism was proposed for the adsorption of the inhibitor, which explained the increase in protective properties with an increase in the length of the alkyl substituent. The high hydrophobicity of the aliphatic fragment, not involved in the chemisorption process, additionally prevents the acid solution from contacting the metal surface, while the heterocyclic moiety ensures the sorption of the inhibitor on the metal surface. As a result, it was shown that derivatives of the homologous series of 3-alkyl-5-aminotriazole are suitable as inhibitors of acid corrosion of ST-3 steel. The minimum length of a hydrocarbon radical at which significant inhibitory activity was observed is 7 carbon atoms. Protection degrees of 65–85% were achieved when 3-heptyl-5-amino-1H-1,2,4-triazole additives at a concentration of at least 2 g/L were added to the hydrochloric acid solution.

Natural Product-Derived Phosphonic Acids as Corrosion Inhibitors for Iron and Steel.

Organic acids, typically derived from an oil-based value chain, are frequently used as corrosion inhibitors in industrial metal working fluids. The criteria for selection of these corrosion inhibitors have changed in the last decades, and are today not only performance-driven, but influenced by ecological considerations, toxicity and regulatory standards. We present scalable semisynthetic approaches to organic corrosion inhibitors based on phosphonic acids from renewable resources. They have been evaluated by chip filter assay, potentiodynamic polarization measurements, electrochemical impedance measurements and gravimetry for corrosion protection of iron and steel in an aqueous environment at slightly alkaline pH. The efficacy of several phosphonic acids tested was found to be strongly dependent on structural features influencing molecular self-assembly of protective layers, and the solubility of salts formed with di- and trivalent cations from the media or formed during corrosion. A carboxyphosphonic acid (derived from castor oil) was found to have remarkable anticorrosive effects in all media tested. We attribute the anticorrosion properties of this carboxyphosphonic acid to the formation of particularly stable protective layers on the metal surface. It might thus serve as a commercially attractive substitute for current acidic corrosion inhibitors, derived from renewable resources.

Effective Inhibition of Carbon Steel Corrosion by Waterborne Polyurethane Based on N-tert-Butyl Diethanolamine in 2M HCl: Experimental and Computational Findings

The efficiency of corrosion inhibition for waterborne polyurethane based on N-tert-butyl diethanolamine (tB-WPU) is investigated using different techniques. Corrosion weight loss, open circuit potential experiments, electrochemical impedance spectroscopy, and potentiodynamic polarization measurements show that both a commercial reagent and a polyurethane-based inhibitor prevent corrosion at increasing temperature to 50 °C. At 75 °C, the activity of both reagents is reduced. In stirring conditions, the effectiveness of acid corrosion inhibition (25 °C, 500 ppm) drops abruptly from 89.5% to 60.7%, which is related presumably to the complexity of binding the polymer molecules to the metal surface. As follows from thermodynamic calculations, the adsorption of tB-WPU on the metal surface in 2M HCl can be treated as a physisorption. Model quantum–chemical calculations support the experimental studies and elucidate the nature of steel surface–inhibitor molecule chemical bond, which is realized mainly by carboxyl and amino groups. It is concluded that WPUs can be considered as a perspective alternative to commercial oilfield reagents due to their versatility.

Corrosion Inhibition and Adsorption Mechanism of PVP for Mild Steel in 1.0 M H2SO4: Experimental and Theoretical Approach

Aim:Corrosion of mild steel pipe line when exposed to dilute sulphuric acid is a very serious problem for people in the industry and they are in constant search of highly efficient corrosion inhibitors for acidic medium. For designing new corrosion inhibitors, a through knowledge of corrosion and adsorption mechanism is required.Background:Pitting, cracking and uniform types of corrosion are very common forms of corrosion in dilute sulphuric acid medium. A highly efficient acid corrosion inhibitor is required to minimize all these three forms of corrosion.Objective:The objective was to provide a solution for pitting, cracking, and uniform types of corrosion and to study corrosion and inhibition mechanisms so that highly efficient corrosion inhibitors can be designed.Methods:Polyvinyl pyrrolidone (PVP) was explored as a corrosion inhibitor for mild steel in 1.0 M H2SO4 by experimental and theoretical techniques. Experimental techniques used were impedance, weight loss, metallurgical microscopy, and polarization. Theoretical techniques used were DFT, MD simulation, Frontier molecular orbital, Langmuir, and Frumkin adsorption. Theoretical parameters like interaction energy, adsorption energy, Fukui function, chemical potential, electron density distribution, HOMO/LUMO eigenvalue, etc., help in understanding the mechanism of adsorption of PVP on the Fe (110) surface.Results:Experimental results were supported by theoretical studies. A linear relation was observed between PVP concentration and inhibition efficiency. A maximum of 85.92% inhibition efficiency was observed with a regression coefficient of 0.998. The pore length, the number of pits, and cracks intensity decrease with the concentration of PVP. The waste dilute H2SO4 after the weight loss study was investigated for its biocompatibility and was found to be within the acceptable limit.Conclusion:PVP was proved to be a highly efficient acid corrosion inhibitor for mild steel in 1.0 M H2SO4 medium.

Derivatives of pyrylium and berberine perchlorate as inhibitors of hydrochloric acid corrosion of steel

Новые технологии, Химическая промышленность, Химическая технология, Научные журналы, Защита от коррозии, Технология металлов, Свойства материалов, Технические журналы, Наука и технологии, Справочная литература, Научные разработки

Synthesis and potential applications of aminoantipyrinoanthracenyl imine as corrosion inhibitor of mild steel in H2SO4 medium

In the present investigation, a simple and facile method for the synthesis of a novel heterocyclic compound aminoantipyrinoanthracenyl imine (AAPAI) was reported using microwave assisted synthesis and probing their corrosion inhibiting nature towards the corrosion of mild steel (MS) in acidic medium. AAPAI was synthesized through microwave assisted reactions of 4-aminoantipyrine and 9-anthracene and characterized using FT-IR, UV-visible and 1H-NMR spectroscopy. The as-prepared AAPAI was utilized as a corrosion inhibitor of mild steel (MS) in H2SO4 medium. The acid corrosion inhibition effect of AAPAI is analyzed by weight loss measurement, electrochemical characterization like potentiodynamic polarization (PDP) and electrical impedance spectroscopy (EIS) and morphological characterization using a scanning electron microscope (SEM). Weight loss measurements suggested that the inhibition efficiency increases with an increase in AAPAI concentration whereas it slightly decreases with temperature. EIS studies showed the increase in charge-transfer resistance () with AAPAI concentration in the acid solution indicating the ability of AAPAI to prevent the corrosion of MS due to the formation of a preventive film on MS with a maximum efficiency of 86.4% at 1.5 mM concentration. Besides, PDP results demonstrate that the AAPAI molecule behaves like a mixed-type inhibitor. Further, morphological characterization using SEM revealed the protecting ability of AAPAI from corrosion. The adsorption of AAPAI on MS surface follows Langmuir adsorption isotherm and the adsorption of AAPAI on MS involves both chemisorption and physisorption.

Weight Loss, Thermodynamics, SEM, and Electrochemical Studies on N-2-Methylbenzylidene-4-antipyrineamine as an Inhibitor for Mild Steel Corrosion in Hydrochloric Acid

The use of N-2-methylbenzylidene-4-antipyrineamine as an acid corrosion inhibitor for mild steel surfaces in hydrochloric acid is discussed in this article by means of weight loss, electrochemical impedance spectroscopy (EIS), and scanning electron microscopy (SEM) methods. The experimental findings exhibited that N-2-methylbenzylidene-4-antipyrineamine is a significant corrosion inhibitor for the mild steel in 1.0 M HCl solution and that its protection efficiency touches the peak at 5 × 10–4 M, exhibiting 91.8% for N-2-methylbenzylidene-4-antipyrineamine. The inhibitory efficiency increases as the inhibitor concentration rises and reduces as the temperature rises. Temperature has a significant impact on corrosion and blocking activities, which is extensively examined and explained. According to the gravimetric results, the examined inhibitor inhibits mild steel surface corrosion by providing a barrier at the metal–hydrochloric acid medium interface. Thermodynamic characteristics were combined with a quantum chemistry investigation using density functional theory to provide more insight into the inhibitory effect mechanism. The tested inhibitor adsorbs on the mild steel surface based on Langmuir’s adsorption isotherm method.