Our study focuses on enhancing the antioxidant potential of saffron petals extract (SPE) as a sustainable corrosion inhibitor for aluminium (Al) in a 3.5% NaCl solution. The phytochemical screening ...and antioxidant activity are identified. Various investigative methodologies, including experimental techniques such as Electrochemical Impedance Spectroscopy (EIS) and Potentiodynamic Polarization (PDP), were employed to evaluate the effectiveness of this compound in inhibiting corrosion. Computational analysis, involving Density Functional Theory (DFT) and Molecular Dynamics (MD) simulations, were utilized to carry out a Theoretical study on the main constituents of SPE. The surface characteristics and composition of the corroded Al were examined using a combination of Scanning Electron Microscopy (SEM), Energy-Dispersive X-ray Spectroscopy (EDX) and Fourier Transform Infrared Spectroscopy (FT-IR). The Electrochemical results suggest that the effectiveness of the inhibitor was dependent on its concentration, reaching 95.11% at 500 ppm of SPE. The PDP indicates that mixed inhibition control effectively slowed down the corrosion of Al. Furthermore, the adsorption behaviour of SPE onto Al follows to the Langmuir isotherm model. SEM, EDX and FT-IR analyses further verified significant alterations in the surface morphology and roughness of Al and confirming the successful formation of a protective layer on the Al surface. Ultraviolet-Visible spectroscopy (UV-Vis) reveals evidence of interaction between Al and the SPE molecules. Computational studies substantiated these observations, demonstrating the reactivity and adsorption patterns of the evaluated major bioactive molecules of SPE on the Al surface.
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•The experimental results confirmed the inhibition efficiency of SPE.•SPE demonstrated exceptional inhibitory performance over 24 hours of immersion.•SEM and FT-IR confirmed the formation of a protective layer by SPE and Al cations.•MD and DFT offered valuable insights into the adsorption of some SPE's molecules.
Addressing the ongoing issue of carbon steel corrosion, this study evaluates the corrosion inhibition performance of two eco-friendly pyridinium-based ionic liquids, ...4-(dimethylamino)-1-nonylpyridin-1-ium Bromide (4DMN) and 4-(dimethylamino)-1-(prop-2-yn-1-yl)pyridin-1-ium Iodide (4DMP), in a 3.5 wt% NaCl solution. Weight loss tests, electrochemical impedance spectroscopy (EIS), potentiodynamic polarization (PDP), quantum chemical calculations (QCCs), and molecular dynamics (MD) simulations were employed to carried out experimental and theoretical studies. Both 4DMN and 4DMP showed concentration-dependent inhibitory effects with 94 % and 92 % effectiveness, respectively. Potentiodynamic data showed that these compounds control both anodic and cathodic reactions without changing the corrosion mechanism. EIS results indicated a decrease in double-layer capacitance, suggesting adsorption of IL molecules on steel surface. Over a 60-h period, 4DMN maintained its effectiveness, although it decreased at higher temperatures. Surface analyses using Field Emission Scanning Electron Microscopy (FE-SEM) and Atomic Force Microscopy (AFM) showed improvements in surface morphology and roughness. Computational studies supported these findings, showing the reactivity and adsorption patterns of the ILs on the Fe (110) surface. Overall, this study contributes to understanding how pyridinium-based ILs can be used for effective and sustainable corrosion control.
In petrochemical engineering, a pressing challenge is the corrosion of N80 carbon steel (N80-CS) in strong acidic conditions like 15 wt% HCl, impacting both mechanical integrity and economic ...viability. Herein, the corrosive behavior of N80-CS in a 15 wt% HCl solution was evaluated with two thiazolidinediones, (Z)− 5-benzylidenethiazolidine-2,4-dione (BT) and 5-(4-fluorobenzylidene) thiazolidine-2,4-dione (FBT). The surface and interface phenomena were evaluated using electrochemical testing, Scanning electron microscope (SEM), atomic force microscopy (AFM), and computational modelling. Electrochemical impedance spectroscopy (EIS) revealed that, at optimum concentrations, the polarization resistance (Rp) manifested a notable increase from an initial 5.51 Ω cm2 to 80.46 and 39.64 Ω cm2 when BT and FBT were introduced, respectively. This corresponded to inhibition efficiencies of 93% for BT and 86% for FBT. This results in a substantial reduction in effective double layer capacitance due to the adsorption of inhibitor molecules. The Rp values of BT compound peaked at 158.02 Ω cm2 after a 24-hour immersion period, later declining to 82 Ω cm2 after 42 h, thus evidencing the enhanced stability of the inhibitor’s protective layer on the steel surface. The potentiodynamic polarization (PDP) technique validated that both compounds function as mixed-type corrosion inhibitors. Their adsorption followed the Langmuir adsorption isotherm model, indicating a mixed mechanism of protection via both physical and chemical interactions between the inhibitor molecules and the steel surface. SEM and AFM analyses further revealed significant alterations in the surface morphology and roughness of N80-CS, affirming the performance of these inhibitors. Ab initio Density Functional Theory (DFT) simulations further supported the experimental results, particularly explaining the superior performance of BT and its exceptional adsorption characteristics. This study confirms the anti-corrosive potential of thiazolidinediones and sets the groundwork for future research and improved inhibitor design.
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The present investigation elucidates the effectiveness of a newly developed organic inhibitor, namely 6,6-diphenyl-2,3-dihydroimidazo2,1-bthiazol-5(6H)-one (PHIT) in inhibiting the corrosion of N80 ...carbon steel (N80-CS) in 15 wt% HCl at 303 K. An integrative approach combining theoretical insights through Density Functional Theory (DFT) and molecular dynamics (MD) simulations with empirical data derived from a suite of analytical techniques (namely, weight loss measurements, electrochemical impedance spectroscopy (EIS), potentiodynamic polarization (PDP), and scanning electron microscopy (SEM)), was employed to assess the corrosion inhibition performance. The research identified the thiazolone fragment as the predominant site of activity within the PHIT molecule. According to EIS results, a significant reduction in the effective double-layer capacitance from 174 (blank) to 36.17 μF/cm2 was registered following the addition of 5 × 10−3 mol/L PHIT to the HCl medium. Moreover, at a low concentration of 10−4 mol/L, the inhibition efficiency reached a maximum of 95 %. The immersion time had a significant effect on the inhibitor's polarization resistance, peaking at 48 h (596 Ω cm2), then experiencing a minor reduction at 72 h (457 Ω cm2), in comparison to the blank measurement at 0.5 h (231 Ω cm2). Besides, the inhibitor demonstrated a high degree of effectiveness across various temperatures with a slight decrement in efficiency from 96.5 % at 303 K to 94 % at 363 K. PDP results confirmed the tested compound as an anodic-type inhibitor. These results affirmed the potential of PHIT as a highly efficacious organic inhibitor for N80-CS in acidic conditions, encouraging further development of its derivatives.
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•PHIT exhibits peak 95 % inhibition on N80-CS in 15 % HCl, proving its potent anti-corrosive property.•DFT and MD simulations identify thiazolone core as PHIT's most reactive site for corrosion inhibition.•EIS results show PHIT's concentration enhances N80-CS polarization resistance, decreasing capacitance.•Despite slight efficacy reduction from 303 K to 363 K, PHIT maintains strong inhibition, suggesting high thermal stability.
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•95% and 98% corrosion inhibition efficiencies of FMI and BIH on N80-CS, revealing failure prevention.•Sustained performance over 5 days, indicating robustness against failure even at ...higher temperatures.•Integrative approach uncovers strong surface interactions, aiding in understanding prevention mechanisms.•SEM/AFM imaging and DFT simulations validate FMI and BIH's effectiveness in corrosion failure mitigation.
This research work is a detailed analysis of the failure mechanisms related to the corrosion of N80 carbon steel (N80-CS) in an acidic environment (15 wt% HCl), commonly encountered in oil and gas industry pipelines. The study investigates the corrosion failure, focusing on the interactions with two isonicotinohydrazide derivatives, namely N'-(Z)-furan-2-ylmethylidenepyridine-4-carbohydrazide (FMI) and N'-(Z)-phenylmethylidenepyridine-4-carbohydrazide (BIH). A combination of experimental and theoretical methods, including weight loss (WL), electrochemical analysis, Field Emission Scanning Electron Microscopy (FE-SEM), Atomic Force Microscopy (AFM), Density Functional Tight Binding (DFTB) semi-empirical calculations, frontier molecular orbital analyses, Fukui function studies, and molecular dynamics simulations, was utilized to identify the corrosion and corrosion inhibition behavior of N80-CS. Experimental findings demonstrated that the inhibition performance of FMI and BIH increased proportionally with the concentration of these inhibitors, demonstrating inhibition efficiencies of 95 %, and 98 %, respectively. This performance was reflected by the enhancement of polarization resistance and a significant reduction in corrosion current density at optimum concentrations. Additionally, they demonstrated exceptional corrosion protection capabilities over prolonged immersion times (up to 5 days) and only a moderate decrease in efficiency with increasing temperature, highlighting their robustness under varying operating conditions. The adsorption behavior of these inhibitors was observed to be in agreement with the Langmuir adsorption model, suggesting physicochemical interactions occurring at the N80-CS surface, specifically covalent bonding. Theoretical studies from DFT, molecular dynamics, and DFTB strengthened experimental results, confirming strong interactions between the inhibitors’ atoms and the surface. Through the integrative experimental and theoretical approach of this study, a comprehensive understanding of the mechanisms and inhibition performance of these studied compounds was achieved. The findings can serve as an invaluable resource towards the development of more efficient corrosion inhibitors, further contributing to the broader field of corrosion and prevention strategies.
•Synthesis of two indolin-2-one derivatives as sustainable corrosion inhibitors.•Compounds exhibited up to 91.54 % corrosion inhibition efficiency in HCl medium.•Surface analysis showed formation of ...a protective layer reducing surface roughness.•Atomistic simulations elucidate physico-chemical adsorption inhibition mechanism.
Effective corrosion management is a pivotal challenge facing various industries and holds crucial importance in aligning industrial processes with sustainability goals. This study focused on the synthesis and evaluation of two indolin-2-one derivatives: (E)-1-allyl-3-(2-(5-oxo-4,4-diphenyl-4,5-dihydro-1H-imidazol-2-yl)hydrazono)indolin-2-one (AIHI) and (E)-3-(2-(5-oxo-4,4-diphenyl-4,5-dihydro-1H-imidazol-2-yl)hydrazono)-1-(prop‑2-yn-1-yl)indolin-2-one (PIHI), as sustainable corrosion inhibitors for N80 carbon steel (N80CS) in a 15 wt. % HCl medium. Chemical, electrochemical, and surface characterization techniques were utilized to evaluate the corrosion inhibition mechanism and the performance of the compounds under investigation. The weight loss method highlighted that tested compounds exhibited promising inhibition efficiencies: 91.54 % for AIHI and 81.97 % for PIHI, respectively, at 303 K, with an outstanding performance of 87.17 % at 363 K for AIHI. The simultaneous addition of AIHI and PIHI in HCl led to a substantial increase in the polarization resistance (RP) and a remarkable decrease in the corrosion current density (icorr). The potentiodynamic polarization (PDP) technique validated that both indolin-2-one compounds function as anodic/cathodic corrosion inhibitors with remarkable anodic effect. Scanning electron microscopy (SEM) and atomic force microscopy (AFM) showed that inhibitors altered steel surface morphology, forming a protective layer, and significantly reduced surface roughness. Atomistic simulations (DFT and SCC-DFTB methods) pointed out that the inhibitors AIHI and PIHI acted by physico-chemical adsorption through donor-acceptor interactions between AIHI or PIHI molecules (s and p orbitals) and the 3d orbitals of Fe(110). The insights obtained serve as a foundation for future advancements in greener corrosion management strategies for sustainable industrial applications, thus reinforcing our commitment to bio-circular economies and sustainable chemistry.
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In this work, two compounds of isonicotinohydrazide organic class, namely (E)-N′-(1-(4-(dimethylamino)phenyl)ethylidene) isonicotinohydrazide (MAPEI) and (Z)-N′-(2-oxo-2, ...3-dihydro-1H-inden-1-ylidene) isonicotinohydrazide (OHEI) were synthesized and evaluated for corrosion protection of N80 steel in a concentrated acidic medium (15 wt.% HCl) at a temperature of 303 K. The weight loss method (gravimetric method) and electrochemical techniques, i.e., electrochemical impedance spectroscopy (EIS) and potentiodynamic polarization curves (PPC), were used to evaluate the inhibition and adsorption characteristics of tested compounds. Further, surface characterization using a scanning electron microscope (SEM) was used to assess the surface morphology of steel before and after inhibition. Weight loss experiments at 303 K and 363 K showed that tested compounds’ performance decreased with the increase in temperature, particularly at low concentrations of inhibitors whereas they exhibited good stability at higher concentrations. Electrochemical tests showed that MAPEI and OHEI inhibitors were effective at 5 × 10−3 mol/L, reaching an inhibition efficiency above 90%. It was also determined that the adsorption of both inhibitors followed the Langmuir adsorption isotherm model. Furthermore, SEM analysis showed that the investigated compounds can form a protective layer against steel corrosion in an acidic environment. On the other hand, the corrosion inhibition mechanism was established from density functional theory (DFT), and the self-consistent-charge density-functional tight-binding (SCC-DFTB) method which revealed that both inhibitors exerted physicochemical interactions by charge transfer between the s- and p-orbitals of tested molecules and the d-orbital of iron. The results of this work are intended to deepen the research on the products of this family to control the problem of corrosion.
N80 carbon steel (N80CS) is recognized for its superior mechanical properties and cost-effectiveness. However, its susceptibility to corrosion, particularly in hydrochloric acid (HCl) environments, ...necessitates the exploration of corrosion inhibitors. This research centers on the evaluation of N′-(Z)-(4-bromophenyl)methylidenepyridine-4-carbohydrazide (BBI) and N′-(1Z)− 1-(4-chlorophenyl)ethylidenepyridine-4-carbohydrazide (CEI), green organic compounds from the isonicotinohydrazide family, as potential eco-friendly and non-toxic inhibitors for N80CS in a 15 wt% HCl solution. An array of investigative methods, including weight loss measurements, electrochemical impedance spectroscopy (EIS), and potentiodynamic polarization (PDP), were employed to examine the corrosion inhibition performance of these compounds for the N80CS surface in a strong HCl medium. Our experimental findings demonstrated that the inhibitors' efficiency was concentration-dependent, enhancing as concentrations ranged from 10−4 mol/L to 5 × 10−3 mol/L. Notably, BBI's inhibitory efficiency varied between 97.6% and 99.28%, while CEI's ranged from 94.31% to 98.44%. PDP curves elucidated the capability of BBI and CEI to control both anodic and cathodic reactions, thereby classifying them as mixed-type corrosion inhibitors. The improved inhibition efficiency was evidenced by the decrease in double-layer capacitance, supporting the formation of a protective layer that delays the corrosion process. Consistent with the Langmuir adsorption isotherm model, our results suggested these inhibitors involved in both physical and chemical interactions with the iron atoms on the steel surface. This protective formation was further corroborated by scanning electron microscopy (SEM) and atomic force microscopy (AFM) analyses, which highlighted a significant reduction in the surface roughness of N80CS. Supplementing our experimental data, theoretical investigations using Density Functional Theory (DFT) and semi-empirical Density functional tight binding (DFTB) simulations were conducted. They confirmed the advantageous reactivity of BBI and CEI, attributable to their molecular structures, which promote facile adsorption onto the Fe(110) surface through covalent bonding. This research provides valuable insights into developing non-toxic and environmentally benign corrosion inhibitors for N80CS in acidic conditions.
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The present investigation is focussed on unveiling the potential of ecologically safe Chitosan derived N-Acylated products (N-ACs) as anti-corrosive agents for mild steel in 0.5 M H2SO4. ...Electrochemical Impedance Spectroscopy (EIS) including potentiodynamic polarization (PDP) and potentiostatic electrochemical impedance were deployed to evaluate their anti-corrosive performance and the results of the same reported N-acylated chitosan derivatives project remarkable inhibition efficiency with the most effective performance of 96.80% at 250 mgL-1. The pronounced inhibition efficiency reported was conclusively accredited to the availability of heteroatoms in modified chitosan which further aid in the formation of a protective barrier over mild steel counterparts. The final acylated products were reported to be mixed type as demarcated by PDP results. Further, the prevention ability of modified chitosan was obtained via adsorption and the Langmuir adsorption model was best seen as suitable in this regard. Surface studies and theoretical modeling including Global Reactivity results, molecular Dynamic Modelling (MD), and Density Functional Bond Tight Binding Results (DFBT) were incorporated to gain insights into the molecular level of interactions between metal and N-ACs.
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•Use of N-ACs to combat corrosion offers eco-friendly and sustainable option.•Corrosion combating ability of N-ACs is related with their structure.•N-ACs molecules adsorb over metal surface as per Langmuir isotherm.•N-ACs-metal interaction energy decides the corrosion combating ability of BCs molecule.•N-ACs decrease the electrolyte-metal surface contact angle.
