Steel In HCl Medium Research Articles

Solanum tuberosum leaf extract as an eco-friendly corrosion inhibitor for Q235-steel in HCl medium: Experimental and theoretical evaluation

Solanum tuberosum leaf extract (STLs), used as a biodegradable corrosion inhibitor, was prepared to mitigate the corrosion rate of Q235 steel in HCl medium. The active inhibitory components existing in STLs were tracked by Fourier transform infrared spectroscopy. Electrochemical measurements, morphological characterization and contact angle tests were combined to evaluate the anti-corrosion performance of STLs at various concentrations and different temperatures, and the results show that the addition of STLs can evidently magnify the charge transfer resistance, expand the double layer capacitance at electric/solution interface, and simultaneously reduce the corrosion current density of Q235 steel in HCl medium with the maximum inhibition efficiency of 91.89 %. The adsorption behavior of STLs on steel was investigated using X-ray photoelectron spectroscopy and adsorption models. It is revealed that the molecules of STLs spontaneously bind to the substrate through chemical and physical action, forming a protective layer to block the diffusion pathway of harsh ions. Furthermore, theoretical calculations confirm that Solanum tuberosum leaves components were adsorbed on steel substrates through donor-acceptor interactions.

'Insights into using a Schiff base as corrosion inhibitor for carbon steel in HCl medium: Experimental and theoretical approaches'

'Insights into using a Schiff base as corrosion inhibitor for carbon steel in HCl medium: Experimental and theoretical approaches'

Study the Effect of “Di-dodecyl amine” as a Corrosion Inhibitor for Carbon Steel in HCl Medium

Numerous organic compounds have been investigated for their potential to reduce corrosion under various circumstances. This study investigated the effects of di-dodecyl amine, an organic chemical, on carbon steel metal corrosion at different temperatures while HCl acid was present. The examination was carried out using accepted methods for polarization, weight loss, and corrosion process testing. The obtained findings demonstrated that the corrosion rate reduces with increasing inhibitor concentration, leading to increased inhibition efficiency. Furthermore, as shown in the weight loss technique, the corrosion rate lowers with increasing surface coverage with organic inhibitor at 313 °C. In the anodic and cathodic polarization methods, as well as in the inhibition efficiency, it is observed to see the cathodic and anodic curves through which the occurrence of the potential and corrosion current is known. The current and corrosion potential decreases with increasing inhibitor concentration. The amines and methyl motiveless in this inhibitor's composition give it their efficacy since they may coat the metal surface and stop corrosion

Origanum Grosii Extracts as Novel Eco-Friendly Corrosion Inhibitors for Mild Steel In HCl Medium.

Two green inhibitors extracted from an endemic species (Origanum grosii (Og)) using two solvents of different polarity (water and ethanol), OgW (aqueous extract) and OgE (ethanolic extract), were used for the anticorrosion of mild steel (M steel) in a 1 M HCl medium. Anticorrosive performance of OgW and OgE was assessed using standard electrochemical techniques, EIS/PDP measurements, weight loss method and SEM/EDX surface analysis. The results show that OgW achieves a maximum inhibition efficiency of 92 % and that the extract in aqueous medium (more polar) is more efficient than the extract in ethanolic medium (less polar). Both extracts act as mixed inhibitors and their corrosion process is predominantly governed by a charge transfer. Concentration and temperature effect was studied and shown that they are two antagonistic parameters for the evolution of inhibitory effectiveness of both OgW and OgE. The adsorption isotherms of the two inhibitors OgE and OgW obey to the Langmuir adsorption model. Moreover, the examination of SEM images and EDX spectra support a deposit of both extracts on the metal surface by an adsorption phenomenon. Besides, theoretical approach of the molecular structures of the major compounds M-OgW and M-OgE and inhibition efficiency was examined via DFT calculations and molecular dynamics simulations and it was consistent with the experimental findings.

Dramatic improvement in corrosion inhibition effect of carboxymethyl cellulose by modified with levodopa: Experimental study and first-principles calculations

Cellulose, as a kind of renewable natural polymer, has great potential as green corrosion inhibitor. However, the low inhibition effect is the obstacle to its practical application. Herein we developed a high efficiency green cellulose derivative corrosion inhibitor, levodopa-carboxymethyl cellulose (LDCMC), by modifying carboxymethyl cellulose (CMC) with levodopa (LD) through a simple amidation reaction. The inhibition effect of CMC for mild steel in HCl medium is dramatically improved with an increase in inhibition efficiency from 56.98% of CMC to 97.27% of LDCMC. The intrinsic nature of the dramatically improved inhibition effect is in-depth unraveled by first-principles calculations based on density functional theory (DFT). CMC and LDCMC can adsorb on the mild steel surface through -OH, -COOH and LD fragment by forming the covalent bonds with steel surface. Benefiting from the additional strong adsorption of the benzene ring in LD fragment, the introduction of LD can significantly enhance the adsorption capacity of LDCMC, which is the intrinsic nature of the dramatical improvement in the inhibition effect of LDCMC.

In-depth experimental assessment of two new aminocoumarin derivatives as corrosion inhibitors for carbon steel in HCl media combined with AFM, SEM/EDX, contact angle, and DFT/MDs simulations

The suitability of the two synthesized hydrazones namely N''-[(4-aminocoumarin-3-yl)methylidene]thiocarbonohydrazide (AMT), and 2-[(4-Aminocoumarin-3-yl)methylidene]hydrazinecarbodithioic acid (AMH) as corrosion inhibitors for N80 carbon steel (N80 CS) metal in acidic hydrochloric solution has been investigated at different concentrations of inhibitors (10–7 to 10–3 M) and different temperatures (298–328 K). The Inhibition efficiency was examined by gravimetric measurements, electrochemical methods supplemented with AFM, SEM-EDX, contact angle measurement, and XRD. The compounds have been characterized using IR, 1H NMR, 13C NMR, and mass spectra. It was found that AMT and AMH exhibit maximum inhibition efficiency of 90.52 and 93.28 %, respectively, at 10−3M against N80 CS corrosion in 1.0 M HCl solutions. The adsorption of inhibitors on the N80 CS surface tends to obey the Langmuir adsorption isotherm. Potentiodynamic polarization results revealed that AMT and AMH functioned as mixed-type inhibitors. All thermodynamic parameters were estimated and discussed. The combination of density functional theory (DFT) and molecular dynamic simulations was used to understand the sites in the AMT and AMH molecules where interaction with the N80 CS surface can occur. Results of the biological test revealed the excellent bioactivity of the AMT and AMH compounds, suggesting AMT and AMH are environmentally friendly corrosion inhibitors.

1,4-Phenylenediamine-based Schiff bases as eco-friendly and efficient corrosion inhibitors for mild steel in HCl medium: Experimental and theoretical approaches

The application of Schiff bases as corrosion inhibitors is one of the economic, practical, and effective techniques to retard metal corrosion in aggressive environment. The continuous exploration of novel, lower-cost, more efficient, and eco-friendly corrosion inhibitors is an everlasting pursuit of excellence. In this study, two 1,4-phenylenediamine-based single Schiff base isomers, (E)-4-((pyridin-2-yl-methylene)amino)aniline (PMAA2) and (E)-4-((pyridin-3-ylmethylene)amino)aniline (PMAA3), were synthesized by one-step reaction. The corrosion inhibition mechanism and structure–activity relationship of PMAA2 and PMAA3 for mild steel in HCl solution were analyzed using electrochemical and weight loss experiments, morphology analysis, density functional theory (DFT) calculation, and molecular dynamic (MD) simulation. The results demonstrated that the corrosion inhibition efficiency of PMAA2 and PMAA3 exhibited an increasing trend with the elevation of inhibitor concentration while showing a slight decrease with the temperature rise. The optimal corrosion inhibition efficiency for 800 mg L−1 PMAA2 and PMAA3 in 1.0 mol L−1 HCl solution is 90.88 % and 91.78 % at 303 K respectively by using weight loss experiment. The electrochemical experiment results indicated that PMAA2 and PMAA3 are mixed-type corrosion inhibitors, with a preponderant control of anodic dissolution. Both the thermodynamics of adsorption and the kinetic of corrosion reaction were evaluated and discussed in detail. Their adsorption upon mild steel complies with Langmuir adsorption isotherm and is involved in phys- and chemisorption concurrently. The results from surfacemorphologyanalysis exhibited that a dense protective film on the surface of mild steel is formed through inhibitor adsorption, which results in changes in the hydrophilicity and hydrophobicity of the metal surface. The calculations of DFT and Fukui index also indicated that both the neutral and pronated species of PMAA2 and PMAA3 possess donor–acceptor interactions with the surface iron atoms through both forward and back-donations. Furthermore,MD simulations further revealed that the neutral molecules as neat-flat and parallel orientation are adsorbed strongly on the Fe (110) surface but the pronated species perform in bent fashion on the Fe (110) surface. Based on the experimental analysis and the theoretical calculation, a possible adsorption and corrosion inhibition mechanism was proposed rationally. These findings display good correlations between the experimental investigation and the theoretical computation and are of fundamental importance to understanding the adsorption and corrosion inhibition mechanisms of the inhibitors.

Adsorption and inhibitive effect of N-[(4{[(Z)-(4-hydroxy phenyl) methylidene] amino} phenyl) sulfonyl acetamide on the corrosion of mild steel in HCl medium

In this study, the inhibitive effects of Schiff’s base, N-[(4{[(Z)-(4-hydroxy phenyl) methylidene] amino} phenyl) sulfonyl acetamide (4-HPMAPSA) on mild steel corrosion in 1.0 M HCl(aq) at different temperatures were investigated using weight loss and scanning electron microscope. The Fourier transform infrared spectrum and X-ray diffraction pattern of 4-HPMAPSA were obtained. It was found that the inhibition effectiveness of 4-HPMAPSA relies on the temperature, 4-HPMAPSA concentration and exposure period. 4-HPMAPSA hinders mild steel corrosion and exhibits a maximum inhibitive efficiency of 88.5 % at 0.5 g of 4-HPMAPSA at 303 K. The activation energy (Ea) value (45.0 to 52.3 kJmol-1) with an average of 47.7 kJmol-1 was obtained for the 4-HPMAPSA-inhibited reaction and 35.1 kJmol-1 for the uninhibited. The thermodynamic values calculated for the 4-HPMAPSA-inhibited reaction show that the process is spontaneous and endothermic. With an R2 value of 0.9646 to 0.9999, Langmuir isotherm best described the 4-HPMAPSA uptake behaviour.

Optimization of the corrosion inhibition performance of novel oxadiazole thione-based Schiff base for mild steel in HCl media using Doehlert experimental design

This study aimed to evaluate the effectiveness of 3-((dicyclohexylamino) methyl)-5-(4-((3, 4-dimethoxybenzylidene) amino) phenyl)-1, 3, 4-oxadiazole-2(3H)-thione (DMOT) in inhibiting the deterioration of mild steel in a 1 M HCl solution. Weight loss and electrochemical measurements were used to assess the inhibition performance and synthesis of DMOT. The characterization of DMOT was conducted through NMR and FTIR measurements, while SEM and AFM were used in the surface analysis. DFT calculations were used to investigate the chemical and theoretical properties of DMOT. The results of electrochemical measurements showed that the inhibition efficiency increased as the concentration of the inhibitor increased, with an optimal concentration reaching an inhibition efficiency of 99.17%. Polarization curves revealed that DMOT molecules behaved as a mixed-type inhibitor, with adsorption following the isotherm of Langmuir. The adsorption of DMOT on the corroded metal's surface was verified by SEM and AFM investigations. Using quantum chemical calculations, the quantum chemical properties of the DMOT were evaluated.

Detailed experimental performance of two new pyrimidine-pyrazole derivatives as corrosion inhibitors for mild steel in HCl media combined with DFT/MDs simulations of bond breaking upon adsorption

The corrosion inhibitory potency of two new pyrimidine-pyrazole derivatives, namely N-((3,5-dimethyl-1 H-pyrazol-1-yl) methyl) pyrimidin-2-amine (PPA) and ethyl 5-methyl-1-((pyrimidin-2-yl amino) methyl)− 1 H-pyrazole-3-carboxylate (PPC), was evaluated by mass loss measurements and electrochemical assays for mild steel (MS) in 1 M HCl at 308 K. In this survey, PPA and PPC products were chosen as inhibitors owing to their environmentally friendly formulation and biodegradability, which aligns with the growing demand for sustainable compounds. Besides, the molecular structure of PPA and PPC was precisely designed to provide higher effectiveness towards corrosion. The derived results revealed that the inhibition activities of both PPA and PPC were enhanced with concentration increase reaching maximal values of 91.15% and 92.39% for PPA and PPC, respectively. Conversely, the mitigation potency dropped by approximately 42.28% (for PPA) and 31.30% (for PPC) as the temperature increased from 308 to 348. PDP plots revealed that PPC and PPA is mixed type inhibitor in 1 M HCl. The adsorption mechanisms of the two inhibitors was examined on micro/nano level with scanning electron microscopy (SEM) and X-ray photoelectron spectroscopy (XPS). The derived outcomes indicated high inhibition performance owing to the adsorption of PPA and PPC on MS surface, forming thus a shielding layer that precludes the MS dissolution in the acidic solution. The experimental findings were further confirmed by theoretical descriptors obtained from DFT and Molecular dynamics simulation (MDS) investigations.

Optimization of the corrosion inhibition performance of 2-mercaptobenzothiazole for carbon steel in HCl media using response surface methodology

In this work, the corrosion inhibition performance of 2-mercaptobenzothiazole (2-MBT) was investigated for carbon steel in 1 M HCl by examining the simultaneous effects of temperature, immersion time, and inhibitor dosage. Design and optimization of the corrosion inhibition have been performed using response surface methodology (RSM). The effectiveness of the inhibitor was analyzed by determining the corrosion rate (CR) and corrosion inhibition efficiency (CIE) using the experimental weight loss method. Based on experimental data and using ANOVA (analysis of variance), two high-precision models have been established to predict CR and CIE. The results depicted that the impact of concentration and temperature on CR and CIE was stronger than immersion time. It was observed that at low concentrations (10–50 ppm), the inhibition performance of 2-MBT was not significant. Increasing the temperature from 30 to 70 °C remarkably decreased CIE by about 14–20% and increased CR by 8–14 mm/y. In addition, it was found that adding 140–160 ppm of 2-MBT at low-to-mean temperature levels (30–50 °C) has the greatest interaction effect on the inhibition performance. In this case, the CIE was more than 92% and CR less than 1 mm/y. Moreover, the process was numerically optimized to “maximize” CIE and “minimize” CR. The results of numerical optimization indicated that optimal conditions for maximum corrosion inhibition performance of 2-MBT (CIE = 94.92%, and CR = 0.72 mm/y) were obtained to be 140 ppm, 34 °C, and 70 h. Furthermore, the type of adsorption of 2-MBT has been examined in the immersion time and temperature ranges of 5–105 h and 30–70 °C. Four models of isotherm for the adsorption analysis were used: Langmuir, Freundlich, Temkin, and Flory Huggins. The best results were observed using the Langmuir isotherm.The presence of both physical and chemical adsorption of 2-MBT was detected. This finding was supported by the range of values for the free energy of adsorption, spanning from −33.72 to −37.16 kJ.mol−1.

Synthesis of multi donating sites grafted on graphene oxide nanosheets: Anti-corrosion study for mild steel in 1 M HCl with DFT calculations

The functionalization of graphene oxide of Sulphate and Phosphate functionalized graphene oxide nanomaterials were investigated as corrosion inhibitors for mild steel in HCl media by employing weight loss, electrochemical, surface, and computational methods. The graphene oxide (GO) was synthesized from industrial waste material graphite. The GO and seven functionalized GO were characterized by the FTIR, SEM, and EDX techniques. The amide-functionalized GO (N-G) exhibited good corrosion inhibition compared to sulfate (S-G) and phosphate (P-G) functionalized GO. It was further observed that the addition of sulfate and/or phosphate functional groups along with amide (NSP-G), showed an improvement in layering structure and exhibited the highest corrosion inhibition (93.78%). FTIR, SEM, EDX, and Contact Angle studies supported the formation of an inhibitive film of NSP-G on the mild steel surface. Density functional theory (DFT) results reveal that the addition of three functional groups in GO enhanced its interaction sites with the mild steel surface. Molecular dynamics (MD) simulation results show the predominantly chemisorption mechanism of NSP-G on the mild steel surface.

Corrosion inhibition effect of mebendazole on 5Cr pipeline steel in 1 M HCl solution

In this manuscript, the ability of (5-Benzoyl-1H-benzimidazol-2-yl) carbamicacidmethylester (mebendazole, MBD) as an inhibitor of corrosion on 5Cr pipeline steel in HCl medium was explored. Corresponding electrochemical tests, immersion tests and other experiments were designed, and at the same time, the ability of mebendazole to inhibit corrosion of 5Cr steel in HCl medium was screened and proved by means of molecular weight simulation calculation analysis process, and its possible anticorrosion mechanism was also revealed. Electrochemical test results show that mebendazole can successfully prevent 5Cr steel from dissolving in HCl medium, and the inhibition efficiency is particularly significant with the increase of mebendazole content. According to the electrochemical impedance test, the highest corrosion inhibition efficiency (η) can reach 94.4 %. The results of immersion weight loss experiment are highly consistent with the electrochemical test data and SEM electron microscope morphology. From the theoretical calculation results, it can be found that under neutral conditions and protonated mebendazole molecules have lower energy gaps and higher dipole moments in solvated and unsolvated environments, and can Parallel adsorption on the metal surface, which also corresponds to its efficient corrosion inhibition performance. In addition, through comparison, it is found that the protonated mebendazole molecule under solvation conditions has the highest binding energy, that is, it is the easiest to interact with 5Cr steel and presents the best anti-corrosion performance.

Heterocyclic group end-capped polyethylene glycol: Synthesis and used as corrosion inhibitors for mild steel in HCl medium

In this work, two categories of water-soluble polymeric corrosion inhibitors (CIs) are contributed. These CIs are composed by polyethylene glycol (PEG) middle segment and oleic imidazoline (or thiophene) end groups, respectively labeled as OIM-PEG-OIM and Th-PEG-Th. Two facile synthetic strategies involve epoxy-amino reaction and thiol-acrylate Michael addition were employed. Both Fourier transform infrared (FTIR) spectroscopy and nuclear magnetic resonance (NMR) spectroscopy verified that a series of target products were successfully obtained. The solution transmittance measurements indicated that with the increase of the PEG segment length, the water solubility of CIs enhanced. And these obtained CIs exhibit somewhat surface activity and could reduce the solution surface tensions to a certain extent. The inhibition efficiencies of these CIs for mild steel in HCl medium were evaluated by weight loss measurements, potentiodynamic polarization, and electrochemical impedance spectroscopy (EIS). It was found that both OIM-PEG-OIM and Th-PEG-Th show an improved corrosion inhibition efficiency as compared to PEG. And as compared to heterocyclic compounds, introduction of PEG segment showed a negligible influence on their performances. Both CIs can form chemisorption on the metal surface, and the adsorption process follow Langmuir adsorption mechanism. OIM-PEG-OIM exhibit superior inhibition performance and stability as compared to Th-PEG-Th, which can be attributed to the fact that OIM-PEG-OIM bearing two long hydrophobic alkyl end groups. Scanning electron microscope (SEM) observations as well as atomic force microscopy (AFM) measurements also confirmed both OIM-PEG-OIM and Th-PEG-Th could serve as water-soluble CIs for mild steel.

Candle soot derived carbon dots as potential corrosion inhibitor for stainless steel in HCl medium

Candle soot derived carbon dots as potential corrosion inhibitor for stainless steel in HCl medium

Corrosion Inhibition Performance and Adsorption Mechanism of Novel Quinazoline Schiff Base on Low Alloy Steel in HCl Media

Corrosion Inhibition Performance and Adsorption Mechanism of Novel Quinazoline Schiff Base on Low Alloy Steel in HCl Media

Mechanistic insight into adsorption and anti-corrosion capability of a novel surfactant-derived ionic liquid for mild steel in HCl medium

A novel cetylpyridinium picrate ionic liquid (CPP) was synthesized and investigated for its corrosion inhibition trait on mild steel (MS) substrate in 1 M HCl. The molecular structure of CPP was elucidated by FT-IR and NMR spectroscopy. Gravimetric experiment, electrochemical impedance spectroscopy (EIS), and potentiodynamic polarization technique (PP) were used to quantify the corrosion inhibition efficiency of CPP. Gravimetric results at 30 °C showed an appreciably high inhibition efficacy of 90.79% at an extremely low concentration of CPP (8 × 10−7 M) which is further raised with temperature attaining maximum protection of 99.04% at 70 °C at the same concentration. Adsorption of CPP at MS-electrolyte interface was ideally compatible with Langmuir adsorption isotherm. Surface analysis by X-ray photoelectron spectroscopy (XPS), energy dispersive X-ray spectroscopy (EDS), contact angle measurement, and FT-IR spectroscopy confirms that CPP forms an organic–inorganic hybrid protective layer to prevent the surface from corrosive ions. Scanning electron microscopy (SEM) micrographs accentuated reduced heterogeneity of metal surface in the presence of adsorbed CPP. The computational methods (DFT, fukui indices calculation, and MD simulation) were exploited to envisage the inhibition mechanism of CPP.

Exploration of imidazol-4-methylimine thiourea as effective corrosion inhibitor for mild steel in hydrochloric medium: Experimental and theoretical studies

Mild steel is considered to be the most common engineering material and the key problem is its susceptibility to corrosion, a problem that can be effectively addressed by corrosion inhibitors. In this work, thiosemicarbazide chain was innovatively used for modifying the imidazole ring to improve the inhibition effect of imidazole compound and thus a high-effective corrosion inhibitor of imidazol-4-methylimine thiourea (MIT) for mild steel in HCl medium was obtained. The inhibition performance of MIT was evaluated by gravimetric measurements, electrochemical tests, and surface analyses. The results indicated that the optimal concentration of MIT was 200 mg L−1 in 1.0 M HCl solution at 298 K, with an inhibition efficiency of 93.7 %. The adsorption of MIT molecules on mild steel was demonstrated to be an exothermic process according to the Langmuir adsorption isotherm, belonging to a mixed adsorption mechanism of physical and chemical adsorption (ΔGads° = −31.87 kJ mol−1, 298 K), which effectively retards the MS corrosion process by blocking both anodic and cathodic reactions. Furthermore, theoretical calculations based on density functional theory and molecular dynamics simulations indicate that the corrosion inhibition mechanism of MIT molecules is mainly attributed to two effective ways, involving shielding effect of the MIT-adsorption film with multiple anchors and reduction of attacking ions.

Efficient inhibition of mild steel corrosion in acidic medium by novel pyrimidine derivatives: Inhibitive effect evaluation and interface adsorption mechanism

In the pickling, oil well acidification, and other industrial processes, mild steel would suffer from severe corrosion in the acidic environment. In this work, two novel pyrimidine derivatives, 2-Benzylthio-6-methylpyrimidin-4(3H)-one (BMPO) and 4-Benzyloxy-2-benzylthio-6-methylpyrimidine (BBMP), were synthesized through nucleophilic substitution reaction, and used as eco-friendly corrosion inhibitors for mild steel in HCl medium. The corrosion inhibition properties of BMPO and BBMP were investigated using electrochemical tests, surface analyses, and theoretical calculations. The experimental results indicate that BMPO and BBMP have superior inhibition effect, with high inhibition efficiency (99.28% and 99.69% at 0.6 mM) and good corrosion inhibition stability. Theoretical calculations reveal that the interface adsorption of BMPO and BBMP is achieved by the bonding of N, S, O atoms and the benzene ring to steel surface. The protonation of BMPO and BBMP molecules could further promote their adsorption. Compared to BMPO, the modification with more benzyl groups lowers the polarity and increases the hydrophobicity of BBMP. Then BBMP molecules could adsorb on steel surface to create a hydrophobic film with a large coverage, which accounts for the better corrosion inhibition effect of BBMP.

Diazenyl derivatives as efficient corrosion inhibitors for mild steel in HCl medium: Gravimetric, electrochemical and computational approach

. In present investigation diazenyl derivatives, namely, (E)-4, 4(E)-4, 4′-(((4-(2-amino-6-phenyl-2H-1, 3-thiazin-4-yl) phenyl) diazenyl) methylene) bis (6-phenyl-6H-1, 3-thiazin 2amine) (ATPA) and (E) 1(4((bis (5-amino1, 3,4- thiadiazol-2-yl) methyl) diazenyl) phenyl) ethanone (ATPE) were synthesized and used as corrosion inhibitor for mild steel (MS) in 15 % HCl solution. Corrosion inhibition studies were performed by weight loss, electrochemical impedance spectroscopy (EIS) and potentiodynamic polarization methods. Potentiodynamic polarization result demonstrates that ATPA and ATPE offered inhibition efficiency of 97.11 and 96.02 %, respectively at 200 ppm concentration and 303 K temperature. Calculated standard free energy of adsorption values were found in the range of −38.47 to −40.84 kJmol−1 for ATPA and −36.91 to −39.19 kJmol−1 for ATPE, suggesting the mixed type adsorption of ATPA and ATPE on MS surface. The adsorption of ATPA and ATPE on MS surface obeyed Langmuir adsorption isotherm. Morphological analysis performed on uninhibited and inhibited samples by field emission scanning electron microscopy (FESEM), energy-dispersive X-ray spectroscopy (EDX), atomic force microscopy(AFM)and X-ray photoelectron spectroscopy(XPS) techniques suggested the formation of protective layer of inhibitor molecules on MS surface. According to polarization results, both compounds behave as anodic inhibitors. Theoretical data of ATPA and ATPE obtained from Density functional theory (DFT), Monte Carlo simulation (MCS) and Molecular dynamic simulation (MDS) supports the experimental observations.