Design and evaluation of a MgO@MnO2@graphite hybrid nanostructure for enhanced acid corrosion protection of carbon steel

Corrosion protection of carbon steel in acidic media by expired bupropion drug; experimental and theoretical study

Two new chitosan derivatives, polyamine grafted chitosan copolymers have been synthesized for corrosion protection of carbon steel in acidic medium. First, methyl acrylate graft chitosan copolymer (CS-MAA) was prepared by the reaction of chitosan (CS) and methyl acrylate (MAA) via the Michael addition reaction. Then, CS-MAA was reacted with ethylene diamine (EN) and triethylene tetramine (TN) respectively to synthesize ethylene diamine grafted chitosan copolymer (CS-MAA-EN) and triethylene tetramine grafted chitosan copolymer (CS-MAA-TN), and the structures were characterized by Fourier-transform infrared spectroscopy (FT-IR). At last, the corrosion inhibition activities on Q235 carbon steel were investi- gated by using gravimetric measurements, metallographic microscope, potentiodynamic polarization and electrochemical impedance spectroscopy (EIS) measurements. The compounds CS-MAA-EN and CS-MAA-TN show an appreciable corrosion inhibition property against corrosion of Q235 carbon steel in 5% HCl solution at 25 o C. It has been observed that CS-MAA- EN shows greater corrosion inhibition efficiency than CS-MAA-TN. The inhibition efficiency of CS-MAA-EN was close to 90% when the mass fraction concentration was 0.2%~0.3%; the inhibition efficiency of CS-MAA-TN was close to 85% when the mass fraction concentration was 0.02%. The present work provided very promising results in the preparation of green cor- rosion inhibitors.

This study presents a comprehensive electrochemical and theoretical evaluation of two naturally occurring organic compounds, Rhamnose and Salicin, as green corrosion inhibitors for carbon steel in 1 M HCl. Electrochemical techniques including Potentiodynamic Polarization (PDP), Electrochemical Impedance Spectroscopy (EIS), and Electrochemical Frequency Modulation (EFM) were employed to assess inhibition performance. At a concentration of 1.0 × 10−3 M, Salicin achieved a maximum inhibition efficiency of 96.10%, while Rhamnose reached 91.91%, as determined by PDP. EIS analysis revealed a significant increase in charge transfer resistance (Rct) from 19.05 Ω cm2 (blank) to 172.27 Ω cm2 for Salicin and 121.65 Ω cm2 for Rhamnose. The adsorption behavior followed the Langmuir isotherm, with calculated free energies of adsorption of −33.21 kJ mol−1 for Salicin and −32.59 kJ mol−1 for Rhamnose, indicating spontaneous mixed-mode adsorption. Density Functional Theory (DFT) calculations revealed that Salicin possesses a lower energy gap (ΔE = 6.321 eV) and higher electron transfer capability (ΔN = 0.943) compared to Rhamnose (ΔE = 8.767 eV, ΔN = 0.783), suggesting superior reactivity and adsorption potential. Adsorption locator simulations confirmed stronger binding of Salicin to Fe(110) surfaces, with an adsorption energy of −230.86 kcal mol−1versus −83.58 kcal mol−1 for Rhamnose. These findings highlight the potential of Salicin as a highly efficient, eco-friendly corrosion inhibitor and demonstrate the value of integrating molecular-level insights into inhibitor design.

The inhibition efficiency and adsorption affinity were investigated for two novel compounds, namely: 6-methoxy-2-naphthyl-[2, 2’-bithiophene]-5-carboxamidine hydrochloride salt (MA-1440) and 5'-(4-chlorophenyl)-2, 2’-bifuran-5-carboxamidine hydrochloride salt (MA-1456). The inhibition study was conducted on carbon steel surface in 1.0 M HCl with different inhibitor doses and different temperature levels, to investigate the optimum dose and preferable temperature. The performed investigation included chemical, electrochemical, instrumental, and quantum computation techniques. A chemical technique was accomplished by using weight-loss measurements. Different factors were studied using weight-loss measurements in order to reach the maximum inhibition efficiency. The adsorption study revealed that the examined inhibitors obey the Langmuir adsorption isotherm and are chemically adsorbed on the steel surface. The electrochemical measurements were accomplished through the electrochemical impedance (EIS) and potentiodynamic polarization (PDP) techniques. Based on the electrochemical measurements, the examined compounds were categorized as mixed inhibitors. The instrumental examination using different techniques namely: scanning electron microscope (SEM), energy dispersive X-ray (EDX), Fourier-transform infrared spectroscopy (FT-IR), and X-ray photoelectron spectroscopy (XPS) confirmed that the considered inhibitors are excellently adsorbed over the carbon steel surface. The extent of the adsorption affinity of these compounds on the carbon steel surface was studied theoretically using quantum computations and Monte Carlo simulation. The theoretical investigation results of quantum chemistry were validated with those obtained by chemical and electrochemical methodologies. All investigations prove that, the tested compounds were adsorbed chemically on the steel surface and achieved maximum inhibition efficiency of, 94.69% and 90.85% for M-1440 and MA-1456, respectively, at the optimum concentration 30 times 10–6 mol L−1 and temperature 328 K.

Bi-layered composites of polydimethylaniline (PDMA) and polypyrrole (PPY) were investigated for corrosion protection of carbon steel. In this work, PNDMA, PPY and PNDMA-AOT/ PPY coatings have been electropolymerization on carbon steel by potentiodynamic and galvanostatic synthesis techniques from aqueous solutions 0.1 M dimethylaniline, 0.1M pyrrole, 0.05 M sodium dioctyl sulfosuccinate (AOT) and 0.3 M oxalic acid. In order to include dioctyl sulfosuccinate ions as dopant in the dimethylaniline, AOT was also added to the polymerization solution of dimethylaniline. Characterization of monolayer and bilayer polymer coatings was carried out by cyclic voltammetry, Fourier transform infrared (FT-IR) spectroscopy and scanning electron microscopy (SEM) techniques. Corrosion behaviour of PDMA-AOT/PPY coated carbon steel was investigated by potentiodynamic polarization and electrochemical impedance spectroscopy (EIS) techniques in 0.5M H2SO4solutions. The results of the corrosion tests showed that PDMA-AOT/PPYI coatings ensure good corrosion protection of carbon steel in aggressive media. Bilayer coatings revealed better corrosion inhibition efficiencies than monolayer coatings A.M.Fenelon, C.B.Breslin, Corros.Sci., 2003,45, 2837P Herrasti, A.I.del Rio, J.Recio, Electrochim.Acta, 2007, 52, 6496.A. Yagan, N.O. Pekmez, A. Yildiz, Prog. Org. Coat., 2006, 57, 314A. Yagan, N.O. Pekmez, A. Yildiz, Electrochim. Acta, 2008, 53, 2474K. Shah, J. Iroh, Synthetic Met., 2002, 132, 35.M. Kraljic, Z. Mandic, L.J. Duic, Corros. Sci., 2003, 45, 181.G. de T. Andrade, M.J. Aguirre, S.R. Biaggio, Electrochim. Acta, 1998, 44, 633. R.Hasanov, S.Bilgic, Progress in organic coatings, 2009, 64, 435-445.B.Zeybek, N.O.Pekmez and E.Kilic, Electrochim Acta, 2011, 56, 9277-9286.J.F. Rusling, S.L. Suib, Adv. Mater., 1994, 6, 922F. Branzoi V. Branzoi and A. Prunã, Revue Roumaine de Chimie, 2012, 57 , 49-55.V. Branzoi,F. Branzoi, L. Pilan, Materials Chemistry and Physics 2009, 118, 197-203.F. Branzoi,V. Branzoi, A. Musina, Surface and Interface Analysis, 2012, 44, 1076-1081

Developing two amino acid derivatives as high-efficient corrosion inhibitors for carbon steel in the CO2-containing environment

Dextran derivatives as highly efficient green corrosion inhibitors for carbon steel in CO2-saturated oilfield produced water: Experimental and theoretical approaches

Seed Extract of Psidium guajava as Ecofriendly Corrosion Inhibitor for Carbon Steel in Hydrochloric Acid Medium

Many naturally-derived organic coating has been proposed for corrosion protection of carbon steel, but its effectiveness is challenged by poor coating adhesion. In this work, chitosan was extracted from Nila tilapia fish scales and coated onto ASTM A36 carbon steel surface by using electrophoretic deposition (EPD) and dip coating (DC) techniques. The work aims at determining the coating technique and process parameters that result in effective corrosion protection of carbon steel in acid solution. The effectiveness of corrosion protection was determined by calculating inhibition efficiency from corrosion parameters obtained by polarization test and electrochemical impedance spectroscopy. Results showed that each coating technique provides different mechanism of corrosion protection. The DC-made coating showed a physisorption mechanism where the steel's corrosion rate increases as the temperature increased. The EPD-coated specimens demonstrated a chemisorption mechanism with its minor change in corrosion rates than those of DC-coated specimens. The DC technique resulted in a higher inhibition (73 %) efficiency and lower corrosion rate than that of EPD (41 %) with some degree of stability over increasing temperature.

Inclusion compounds of dibenzylthiourea with hydroxypropylated-cyclodextrins for corrosion protection of carbon steel in acidic medium

This study explored the potential of a newly synthesized derivative, 2-amino-4-(4-hydroxy-3-methoxyphenyl)-7-methyl-4H-chromene-3-carbonitrile (AHMCC), as a broad-spectrum antibacterial agent and a corrosion inhibitor for carbon steel (C.STL) in 0.5 M HCl solution. AHMCC demonstrated remarkable antibacterial efficacy against Gram-negative (Escherichia coli, Klebsiella pneumoniae) and Gram-positive (Bacillus subtilis, Staphylococcus aureus) bacteria, as evidenced by agar plate tests and cell viability assays. In the corrosion inhibition studies, AHMCC exhibited mixed-type inhibitor behavior as revealed by potentiodynamic polarization (PDP) measurements. The inhibition efficiency increased with rising AHMCC concentration, confirmed by a significant enhancement in charge transfer resistance (R ct) observed in electrochemical impedance spectroscopy (EIS) analysis. Electrochemical frequency modulation (EFM) data with obtained CF2 and CF3 values further corroborated these findings. Langmuir isotherm modeling suggested AHMCC molecules followed a monolayer adsorption pattern on the C.STL surface. UV-visible spectroscopy indicated the formation of a protective layer through chemical interaction between AHMCC and the metal surface. Atomic force microscopy (AFM) provided visual confirmation of this protective film shielding the C.STL from the corrosive environment. Additionally, theoretical calculations supported the proposed adsorption mechanism of AHMCC molecules onto the C.STL surface.

The inhibition effects of synthesized azodye derivatives on carbon steel corrosion in 2.0 M HCl were studied using weight loss, potentiodynamic polarization, and electrochemical frequency modulation (EFM) techniques. Potentiodynamic polarization measurements show that azodye derivatives are mixed-type inhibitors. EFM can be used as a rapid and non destructive technique for corrosion rate measurements without prior knowledge of Tafel constants. The results obtained from weight loss, potentiodynamic polarization and EFM measurements were in good agreement. Adsorption of these inhibitors on the surface on carbon steel follows the Langmuir adsorption isotherm. The surface of carbon steel examined using UV-vis reflectance spectroscopy. Quantum chemical calculations have been performed and several quantum chemical parameters were calculated and correlated with the corresponding inhibition efficiencies.

How does the integration of amino acids enhance the bonding ability of triazine-based inhibitors with iron surfaces: Insights from SCC-DFTB, COSMO-RS and molecular dynamics simulations

Assessing the newly synthesized bio-based amylase-chitosan/cellulose nanocrystals- ZnO composite for enhanced corrosion protection of carbon steel in acidic medium

This work aims to investigate the possible use of the palm kernel cake powder (Elaeis guineensis Jacq.) as corrosion inhibitor for ASTM 1020 carbon steel in acidic media (0.5 mol L−1 HCl). The investigation was carried out using electrochemical impedance spectroscopy (EIS), polarization curves, gravimetric technique and scanning vibrating electrode technique (SVET). Fourier transform infrared spectroscopy (FTIR) and scanning electron microscopy (SEM) were employed as chemical and surface characterization techniques, respectively. The results of the EIS and gravimetric tests showed that the substance acts as an effective corrosion inhibitor and inhibition efficiency (IE) increases according with the increase of the corrosion inhibitor concentration in the aggressive medium. The highest IE of 87% was obtained for the highest corrosion inhibitor concentration used (1.77 g/L). The polarization curves revealed a mixed inhibitor. The adsorption of the studied inhibitor on carbon steel surface obeyed Langmuir isotherm. The SVET measurements did not reveal anodic or cathodic activities in the substrate surface in the presence of the inhibitor, revealing that the corrosion inhibitor was able to block both reactions. FTIR analyses identified in the powder the presence of hydroxyl group, aromatic rings, nitrogen and oxygen in such groups as amines and oleaginous acid, which can be responsible for the inhibitory properties of the whole material. SEM analyses showed that the corrosion process was retarded when the inhibitor was added to electrolyte. The results indicate that the powder of palm kernel cake is promising for use as corrosion inhibition purpose for carbon steel in acidic media.