S.A. Al‐Thabaiti and F.M. Al‐Nowaiser
Oligomer (semicarbaside‐phethalic acid) and its complexes with Fe(III), Co(II) and UO2(II) chloride were prepared and characterised using elemental analysis, spectral (1H NMR…
Abstract
Oligomer (semicarbaside‐phethalic acid) and its complexes with Fe(III), Co(II) and UO2(II) chloride were prepared and characterised using elemental analysis, spectral (1H NMR, infrared and UV‐Vis) and magnetic measurements. Extensive studies suggested that the Fe(III), Co(II), and UO2(II) oligomer complexes were octahedral dimers. Thermal analyses (thermal gravitational analysis (TGA) and differential thermal analysis (DTA)) of the complexes were carried out and the relevant activation energies were calculated. The effect of the oligomer on the corrosion of iron metal in acidic media (2 M H2SO4) was studied. It was found that the oligomer inhibited the corrosion of iron metal in acid media. The corrosion inhibition efficiency of these compounds was calculated based on weight loss and potentiostatic measurements.
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Younes El Kacimi, Mouhsine Galai, Khaoula Alaoui, Rachid Touir and Mohamed Ebn Touhami
The purpose of this paper is to study the effect of silicon and phosphorus content in steel suitable for galvanizing on its corrosion and inhibitor adsorption processes in…
Abstract
Purpose
The purpose of this paper is to study the effect of silicon and phosphorus content in steel suitable for galvanizing on its corrosion and inhibitor adsorption processes in steels/cetyltrimethylammonium bromide combined and KI (mixture)/5.0 M hydrochloric acid systems has been studied in relation to the temperature using chemical (weight loss), Tafel polarization, electrochemical impedance spectroscopy (EIS), scanning electronic microscope (SEM) analysis and Optical 3D profilometry characterization. All the methods used are in reasonable agreement. The kinetic and thermodynamic parameters for each steels corrosion and inhibitor adsorption, respectively, were determined and discussed. Results show that the adsorption capacity for Steel Classes A and B are better than Steel Class C surfaces depending on their silicon and phosphorus content. Surface analyses via SEM and Optical 3D profilometry was used to investigate the morphology of the steels before and after immersion in 5.0 M HCl solution containing mixture. Surface analysis revealed improvement of corrosion resistance of Steels Classes A and B in the presence of mixture more than Classes C. It has been determined that the adsorbed protective film on the steels surface heterogeneity markedly depends on steels compositions, that is, the heterogeneity increases with decreasing silicon and phosphorus content.
Design/methodology/approach
The effect of silicon and phosphorus content in Steels Classes A, B and C on its corrosion and inhibitor mixture adsorption processes in 5.0 M HCl solution has been studied by weight loss, potentiodynamic polarization, EIS and surface analysis.
Findings
The inhibition efficiency of mixture follows the order: (Steel Class A) > (Steel Class B) > Steel Class C) and depends on their compositions in the absence of mixture according on their silicon and phosphorus content, that is, the corrosion rate increases with increasing of the silicon and phosphorus content. A potentiodynamic polarization measurement indicates that the mixture acts as mixed-type inhibitor without changing the mechanism of corrosion process for the three classes of mild steels.
Originality/value
Corrosion rate mild steels in 5.0 M HCl depends on their compositions in the absence of mixture according to their silicon and phosphorus content, that is, the corrosion rate increases with increasing silicon and phosphorus content. The adsorbed protective film on the steels surface heterogeneity markedly depends on steels class’s compositions, that is, the heterogeneity increases with decreasing silicon and phosphorus content.
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Abou-Elhagag A. Hermas, Mostafa H. Wahdan and Eatemad M. Ahmed
This work aims to prepare and characterize of protective anticorrosion phosphate-doped polyaniline (PANI) nanocomposite coatings for stainless steel (SS) in chloride solution.
Abstract
Purpose
This work aims to prepare and characterize of protective anticorrosion phosphate-doped polyaniline (PANI) nanocomposite coatings for stainless steel (SS) in chloride solution.
Design/methodology/approach
PANI composite coatings were electrodeposited from aqueous sulfuric acid solution containing monomer and Al2O3 nanoparticles using cyclic voltammetry technique. Doping by phosphate was done by aging the coated steels for different periods (1–168 h) in phosphate solution. The polymer film composite was investigated by Fourier-transform infrared spectroscopy and scanning electron microscopy techniques. Potential-time, anodic polarization and electrochemical impedance spectroscopy were used to study the protection efficiency of the coatings.
Findings
The Al2O3 nanoparticles were incorporated into the deposited PANI layer but they decreased the deposition of polymer. The nanoparticles and the phosphate anions enhanced the protective PANI layer for passivation and protection of SS in the chloride solution.
Originality/value
The replacement of counter anions by phosphate ions improved significantly the PANI and its nanocomposite as protective coating of SS in chloride solution.
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Alvaro A. Rodriguez, Chelsea N. Monty, Christopher M. Miller, Hongbo Cong and Evan K. Wujcik
The purpose of this study is to develop laboratory techniques to evaluate the inhibition efficiency of salt neutralizer (SN) solutions in the corrosion protection of metal alloys…
Abstract
Purpose
The purpose of this study is to develop laboratory techniques to evaluate the inhibition efficiency of salt neutralizer (SN) solutions in the corrosion protection of metal alloys associated with winter maintenance equipment.
Design/methodology/approach
The corrosion resistance of alloys A36, B36 and B152 treated with SNs was evaluated by accelerated corrosion testing (ASTM B117) and electrochemical polarization curves. Characterization of inhibition solutions was performed by contact angle measurements, scanning electron microscopy, ultraviolet-visible spectroscopy and Fourier transform infrared spectroscopy.
Findings
Salt neutralizer systems act as mixed inhibitors in acidic media by changing the corrosion resistance ability of metal alloys because of the adsorption of surfactant molecules through their hydrophilic heads. The correlation of the corrosion rate of metal alloys and the inhibitor efficiency showed the influence of the SN type, its concentration, its effective adsorption constant and its contact angle on the alloy surface. Salt neutralizers with higher manufacturer’s recommended wash concentrations (MRWC) to critical wash concentration ratio, lower contact angle on the alloy surface and higher Keff were more successful at preventing corrosion on the alloys tested.
Originality/value
The results of this work provide, for the first time, both quantitative and qualitative information of the properties of washing techniques in the use of effective cleaning strategies for protecting winter maintenance equipment from corrosion. Other state departments of transportation facing similar weather conditions will be benefited by identifying measures and techniques to increase the corrosion resistance of their equipment assets.
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Yingxin Goh, A.S.M.A. Haseeb and Mohd Faizul Mohd Sabri
The purpose of this paper is to enhance the understanding on the electrodeposition of various lead (Pb)‐free solder alloys, so that new studies can be carried out to solve…
Abstract
Purpose
The purpose of this paper is to enhance the understanding on the electrodeposition of various lead (Pb)‐free solder alloys, so that new studies can be carried out to solve processing issues.
Design/methodology/approach
The paper reviews the available reports on the electrodeposition of tin (Sn)‐based solder systems and identifies the challenges in this area.
Findings
Compositional control remains a major challenge in this area, where the achievement of desired composition for binary and ternary alloys is subjected to uncertainties. The use of chelating agents in the bath and optimization of parameters can assist the achievement of near‐desired alloy composition. Acidic plating baths are preferred due to their compatibility with photoresists but oxidation of stannous ions causes poor bath stability. Antioxidants, reducing agents and low oxygen overpotential anodes can suppress the oxidation rate and increase the lifespan of plating baths. Apart from chelating agents and antioxidants, various categories of additives can be added to improve quality of deposits. Surfactants, grain refiners and brighteners are routinely used to obtain smooth, fine‐grained and bright deposits with good thermo‐mechanical properties.
Originality/value
The paper provides information on the key issues in electrodeposition of Pb‐free solder alloys. Possible measures to alleviate the issues are suggested so that the electrodeposition technique can be established for mass production of a wider range of solder alloys.
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Ahmad Khajouei, Effat Jamalizadeh and Seyed Mohammad Ali Hosseini
The purpose of this paper was to study the corrosion resistance of AA2024 alloy using surfactant-modified halloysite nanocapsules capable of holding benzotriazole (BTA) as the…
Abstract
Purpose
The purpose of this paper was to study the corrosion resistance of AA2024 alloy using surfactant-modified halloysite nanocapsules capable of holding benzotriazole (BTA) as the corrosion inhibitor and discharging it into the solution.
Design/methodology/approach
The effect of surfactant shells was studied by surfactant-modified halloysite nanotubes fabricated through assembly of two types of cationic surfactants. The zeta potential and size distribution measurements were performed using a Zetasizer Nano. The concentration of BTA during release into the solution was detected by using a UV–vis spectrophotometer. The anti-corrosion activity of nanocapsules as free agents with respect to the AA2024 alloy was investigated using the potentiodynamic scan (PDS) method. An epoxy resin doped with nanocapsules was used as an anti-corrosion coating deposited on the AA2024 alloy. The corrosion protection performance of coatings was studied by using the electrochemical impedance spectroscopy (EIS) method.
Findings
The results indicate that the release of the inhibitor from nanocapsules depends on the surfactant shell components. The PDS results confirmed the feasibility of developing “smart” corrosion protection by inhibitor-loaded nanocapsules. The results of EIS measurements showed that the coating with the nanocapsules exhibited enhanced corrosion protection in comparison with the undoped coating.
Originality/value
The findings of this paper indicate that surfactant-modified halloysite nanocapsules can be added to epoxy resin coatings to improve their corrosion protective properties for the AA2024 alloy.
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Ivan M. Zin, Vasyl I. Pokhmurskii, Sergiy A. Korniy, Olena V. Karpenko, Stuart B. Lyon, Olha P. Khlopyk and Mariana B. Tymus
The purpose of this paper is to study the influence of rhamnolipid biosurfactant complex on the corrosion and the repassivation of a freshly cut Al-Cu-Mg aluminium alloy surface.
Abstract
Purpose
The purpose of this paper is to study the influence of rhamnolipid biosurfactant complex on the corrosion and the repassivation of a freshly cut Al-Cu-Mg aluminium alloy surface.
Design/methodology/approach
The electrochemical methods, supported by quantum-chemical calculations and scanning electron microscopy data, were used.
Findings
It was established that the rhamnolipid biosurfactant effectively inhibits corrosion of the alloy in synthetic acid rainwater. The efficiency of inhibition becomes stronger with the increase of biosurfactant concentration; however, above the critical micelle concentration, the further improvement in inhibition is minor. It is believed that the mechanism of corrosion inhibition is related to the adsorption of the biosurfactant molecule on the aluminium alloy surface and the formation of a barrier film; however, the formation of a complex compound (salt film) between aluminium ions and rhamnolipid on anodic sites of the alloy is not ruled out. In case of surface mechanical activation of the alloy, the biosurfactant molecule effectively prevents corrosion. Furthermore, addition of the biosurfactant to the corrosion environment increases the repassivation kinetics of the alloy by two to four times as compared with an uninhibited environment.
Practical implications
The commercial impact of the study consists in the possibility of obtaining of environmentally safe corrosion inhibitors of aluminium alloys by biosynthesis from renewable agricultural raw materials.
Originality/value
The originality of this paper is to study the effectiveness of “green” corrosion inhibitor based on biogenic product on freshly generated surface of aluminium alloy.
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Elbahi Djaalab, Mohamed Elhadi Samar, Saida Zougar and Rochdi Kherrat
A new electrochemical analysis based on ß-cyclodextrin (ß-CD) was developed for penicillin V (Peni-V) using polyaniline as a conducting polymer.
Abstract
Purpose
A new electrochemical analysis based on ß-cyclodextrin (ß-CD) was developed for penicillin V (Peni-V) using polyaniline as a conducting polymer.
Design/methodology/approach
The preparation of modified electrode involves the incorporation of β-CD with membrane of polyaniline. Polyaniline, incorporating β-CD, was prepared by electrochemical polymerization method in a medium of hypochloride. Cyclic voltammetry and electrochemical impedance have been used to characterize this sensor. The detection and the kinetic study of modified platinum electrode are evaluated.
Findings
Results clearly indicate that β-CDs interfere with the polymerization mechanism with an inhibition factor. The inclusion phenomenon of β-CDs has been studied and applied to detect Peni-V. The principle of this electrochemical sensor is based on the chemical properties of β-CD, which were studied using the cyclic voltammetric method and impedance spectroscopy. The electrochemical behavior of Peni-V at concentrations between 10–8 and 10–2 M was measured versus Ag/AgCl at pH 7.4 and 30°C in a phosphate alkaline buffer. Relationship of Peni-V concentration in logarithmic mathematical form with current in potentiometric method and with resistance in impedimetric method were obtained.
Originality/value
The present study showed that the Pt electrode modified with Polyaniline–β-CD was an excellent candidate for sensitive penicillin analysis. The proposed electroanalytical technique is rapid, simple and inexpensive.
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Heba Abdelrazik Mohamed and Mona Hassan Abdel Rehim
– The purpose of this paper was to protect carbon steel from corrosion with self–aggregated, eco-friendly, water-soluble hyperbranched polyamide-ester (Hb-PAE).
Abstract
Purpose
The purpose of this paper was to protect carbon steel from corrosion with self–aggregated, eco-friendly, water-soluble hyperbranched polyamide-ester (Hb-PAE).
Design/methodology/approach
Hb-PAE was synthesized through bulk polycondensation reaction between maleic anhydride and di-isopropanol amine. Complete structural analysis for the obtained polymer was performed using Fourier Transfer Infra-Red Spectroscopy, 1H NMR, Thermal gravimetric analysis (TGA) and differential scanning calorimetry, and the molar mass was measured using gel permeation chromatography/refractive index. For this study, the surface activity of Hb-PAE with hydroxyl end groups was investigated. Surface tension of 1.0 × 10−6 to 0.1M of both Hb-PAE/H2O and Hb-PAE/1N HCl systems was measured, and the critical aggregation concentration (CAC) in both systems was determined. Hb-PAE was examined as a corrosion inhibitor for plain carbon steel in both neutral (distilled water) and acidic (1N HCl) media. The corrosion of the steel was studied quantitatively by measuring its weight loss in both media in the absence and presence of Hb-PAE. The surface morphology of the exposed steel test samples was examined using scanning electron microscopy.
Findings
It was found that Hb-PAE inhibited corrosion of steel around the CAC, and its corrosion inhibition efficiency was increased by increasing its concentration.
Originality/value
The research can provide a reference for the relationship between the aggregation concentration of the prepared Hb-PAE with its corrosion inhibition efficiency on plain carbon steel. Hb-PAE as a corrosion inhibitor is environmentally acceptable, economical and readily available.