Corrosion Protection Of Carbon Steel Research Articles

One pot graphene-based nanocontainers as effective anticorrosion agents in epoxy-based coatings

A novel nanocontainer using graphene oxide nanoscrolls (GONS) as shell and benzotriazole (BTA) as core is proposed and embedded in epoxy coating for the corrosion protection of carbon steel. BTA/GONS nanocontainer is effectively fabricated by a modified shock-cooling approach. The hybrid material takes the specific shape of graphene oxide sheet spirally wrapped into scroll structure, acting as favorable physical barrier to afford encapsulation performance. A high uptake and storage of BTA in GONS is achieved, showing a loading capacity of 78.40%. The fantastically scrolled structure also provides an effective network to well control the BTA liberation during long-term immersion. The transport of BTA is diverse with pH values. The maximum release capacity of BTA occurs in neutral condition, larger than that in acid or alkaline environment. The liberation for up to 456 h exhibits the steady releasing characteristics of the containers. The corrosion inhibition performance of BTA/GNOS containers was mainly evaluated by electrochemical impedance spectroscopy. In comparison with, the reference epoxy coating, the one modified by BTA/GNOS nanocontainers demonstrate more excellent anticorrosion ability. The successful embedding and homogeneous distribution of BTA-loaded GNOS nanocontainers in epoxy film contributes to the improvement in the corrosion resistance of Q235 carbon steel and the self-healing performance of the coating.

Impedance analysis of film-forming amines for the corrosion protection of a carbon steel

Octadecylamine (ODA) is a well-known organic inhibitor for the corrosion protection of carbon steels. In the present study, electrochemical impedance data analysis was performed to extract physical parameters of the ODA thin film that formed on a P275 carbon steel surface. First, surface observations and contact angle measurements showed the steel surface modification after the ODA treatment linked to the adsorption of an organic hydrophobic thin film. X-ray photoelectron spectroscopy confirmed the presence of a very thin organic layer and revealed the presence of iron oxide/hydroxide underlying the ODA film. The impedance data analysis with a power-law distribution of resistivity in the organic film allowed the permittivity and thickness to be extracted. Finally, from the impedance results with and without ODA, the instantaneous corrosion inhibition efficiency was determined.

Synthesis of Silica/Polypyrrole Nanocomposites and Application in Corrosion Protection of Carbon Steel.

Silica/polypyrrole nanocomposites without dopant (SiO2/PPy) and with oxalate dopant (SiO2/PPyOx) were synthesized using polymerization of pyrrole in the presence of nano SiO2. Synthesized SiO2/PPy and SiO2/PPyOx were characterized by FTIR, SEM, TEM and EDX and their electrical conductivities were determined by CV method through the two-point-electrode without electrolyte. The corrosion protection performance of polyvinylbutyral (PVB) coatings containing SiO2/PPyOx was evaluated and compared with that of pure PVB coatings and of PVB coatings containing SiO2/PPy by electrochemical impedance spectroscopy and adhesion measurement. The results show that electrical conductivities of SiO2/PPy and SiO2/PPyOx were 0.181 and 0.109 S/cm, respectively. The ratio of PPy on SiO2 in SiO2/PPy and SiO2/PPyOx composites was 0.77/1 and the ratio of oxalate on PPy in SiO2/PPyOx composite was 1.24/1. SiO2/PPy and SiO2/PPyOx improved corrosion resistance and adhesion of PVB coatings. The presence of oxalate in SiO2/PPyOx significantly enhanced the effect of SiO2/PPy on the protection performance of PVB coatings.

Corrosion Protection of Carbon Steel by Pongamia glabra Oil-Based Polyetheramide Coatings

Corrosion Protection of Carbon Steel by Pongamia glabra Oil-Based Polyetheramide Coatings

Superhydrophobic oligoaniline-containing electroactive silica coating as pre-process coating for corrosion protection of carbon steel

This paper provided a novel coating system for Q235 steel using electrodeposited oligoaniline modified silica coating (E-M-SiO2) as a pre-process coating, which was prepared by one step coelectrodeposition of a mixture of tetraethyl orthosilicate (TEOS) and N,N′-Bis(4′-(3-triethoxysilylpropylureido)-phenyl)-1,4-quinonenediimine (TSUPQD). Microstructure, contact angle, electroactivity and anticorrosion performance were investigated by FTIR, UV–vis, AFM, SEM, OCA20 contact angle analyzer, CV and CHI-660E electrochemical workstation. The CA test indicated, in comparison with pure silica and sol–gel modified silica hybrid coatings, the electrodeposited modified silica coating exhibited a super hydrophobic performance. The CV test illustrated that the special redox property of aniline trimer was maintained in these modified silica hybrid coatings. More importantly, the anticorrosion effectiveness for Q235 steel in 3.5% NaCl solution was improved by the addition of oligoaniline modified silica as the pre-process coating. By comparison, it turned out that the epoxy/E-M-SiO2 coating system presented the lowest icorr value and the highest |Z|0.01Hz value. The corrosion protection mechanism was the synergistic effect of super hydrophobic nature of E-M-SiO2 pre-process coating and special catalytic capability of aniline trimer unit, which effectively restrained the permeation of corrosion medium and induced the formation of passive films consisted of α-Fe2O3 and Fe3O4 on the Q235 surface.

A New Polymeric Nanocomposite Coating for Corrosion Protection of Carbon Steel in HCl Solution

In the present work, four polymeric nanocomposite PNC coatings were prepared with different concentrations of yttrium aluminum garnet nanoparticles YAG-NPs in polyvinyl butyral PVB matrix. The corrosion protection of the PNC coatings applied on the carbon steel surface was investigated in 1.0 M HCl solution by electrochemical impedance spectroscopy EIS. The YAG-NPs were synthesized by pulse electrochemical method. The formation of YAG-NPs was confirmed through XRD and SEM analysis. The EIS data obtained from the coated samples both without and with YAG-NPs samples were fitted with an equivalent circuit containing two time constants. The protection efficiency values of the PNC coatings were calculated from EIS data. The PNC coating containing 0.025 wt YAG-NPs as the efficient coating showed the best corrosion protection in HCl solution for immersion times up to 28 days.

Improvement of active corrosion protection of carbon steel by water-based epoxy coating with smart CeO2 nanocontainers

Abstract Water-based epoxy coating containing CeO2 nanocontainers was successfully applied on carbon steel for corrosion protection. CeO2 nanocontainers were loaded with the corrosion inhibitor benzotriazole (BTA). Polyelectrolyte multilayers were deposited on the loaded nanocontainers by layer-by-layer assembly method. Responsive release of BTA molecules were studied in water media at different pH values using UV–vis spectroscopy. The anticorrosive performance of the epoxy coatings doped with 0.5 wt% of smart nanocontainers was tested by immersion of the coated carbon steel in 0.5 M NaCl solution. Electrochemical impedance spectroscopy (EIS) was used to estimate the influence of smart nanocontainers on the passive corrosion resistance. The self-healing performance of the coating with modified CeO2 nanocontainers was studied by scanning Kelvin probe (SKP). From results of EIS and SKP, the addition of pH-sensitive nanocontainers into the epoxy resin inhibited the corrosion activities on the metal surface, showing a promising strategy for developing water-based epoxy coatings with long term protection performance.

Application of 1D attapulgite as reservoir with benzotriazole for corrosion protection of carbon steel

The development of active systems to protect metal substrates against corrosion by using inhibitor-loaded nanocontainers is a promising approach for many industrial applications. This study introduces attapulgite as a reservoir for loading a corrosion inhibitor (benzotriazole). As a key component, inhibitor-loaded attapulgite was dispersed in a water-based epoxy coating to protect carbon steel. The release behavior of the encapsulated inhibitor from the attapulgite nanocontainers in response to pH variation was investigated using UV–visible spectroscopy. The corrosion properties of the composite coatings were explored by electrochemical impedance spectroscopy. The coating with inhibitor-loaded attapulgite demonstrated enhanced film barrier properties compared with blank coating. The scratched coating with inhibitor-loaded attapulgite showed increased corrosion resistance relative to that of the blank coating after immersion and hence exhibited an active corrosion protection. The coating's self-healing mechanism can be attributed to the passive film formation on the metal surface promoted by the inhibitor release from the nanocontainers.

Epoxy‐based PANI/zinc oxide/glass fiber nanocomposite coating for corrosion protection of carbon steel

In this work, a nanocomposite based on conductive polyaniline (PANI) was polymerized, via reverse microemulsion polymerization, in the presence of phosphoric acid and dodecylbenzenesulfonic acid. Applied simultaneously, these acids act as dopants, increasing the solubility of PANI in organic solvents. They further improve the corrosion protection performance of PANI by forming phosphate‐metal complex on metal surface. Zinc oxide nanoparticles were added to the PANI mixture before introducing ammonium persulfate. The final product of polymerization was added to an epoxy resin which served as the matrix for the coating. In order to improve coating elasticity, which can enhance coating resistance against impacts, E‐glass fiber (GF) was added to the coating formulation. It was observed that, with an optimized w/w%, the PANI/zinc oxide/GF composite improved the coating characteristics. Coatings were further subjected to stress‐strain and DC polarization tests, and their cross‐sections were investigated at break point by means of SEM. DC polarization plots revealed that the addition of zinc oxide can also shift the corrosion potential of steel toward positive potentials.

Electrochemical and Corrosion Protection Performance of New Polymer Composite Coatings on Carbon Steel in Sulfuric Acid Medium

In this study, galvanostatic electrodeposition mode was used for the synthesis of new composite (Ppy-AOT/PNEA and PNEA/ Ppy-AOT) coatings onto carbon steel of type OLC 45 for corrosion protection. Monolayer poly (N- ethylaniline) (PNEA), polypyrrole (Ppy), dioctyl sulfosuccinate sodium (AOT) and bilayer PNEA/Ppy-AOT and Ppy-AOT/PNEA coatings have been electropolymerization onto carbon steel by galvanostatic synthesis techniques from aqueous solutions 0.1 M N ethylaniline, 0.1M pyrrole, 0.01 M dioctyl sulfosuccinate sodium (AOT) and 0.3 M oxalic acid. In order to include dioctyl sulfosuccinate ions as dopant in the polypyrrole, AOT was also added to the polymerization solution of polypyrrole. The monolayer and bilayer polymers coatings were characterized electrochemically, spectroscopically and morphologically by cyclic voltammetry, Fourier transform infrared (FT-IR) spectroscopy and scanning electron microscopy (SEM) techniques. Corros ion behaviour of PNEA-AOT/PPY coated carbon steel of type OLC 45 was investigated by potentiostatic and potentiodynamic polarization, open circuit potential measurements and electrochemical impedance spectroscopy (EIS) techniques in 0.5M and 1 M H2SO4solutions. The results of the corrosion tests showed that PNEA/PPY-AOT coatings ensure good corrosion protection of carbon steel in aggressive media. Bilayer coatings revealed better corrosion protection efficiencies than monolayer coatings. The new complex nanostructured composite obtained from this process is promising and might lead to industrial applications in the protection of the carbon steel substrates against corrosion. Keywords: nanocomposite films, galvanostatic electrodeposition, corrosion protection, SEM, EIS, FT-IR

Corrosion Protection of Carbon Steel by Zn/PPY mCoating as Layers in 3.5% NaCl

Plate from low carbon steel was took from oil pipelines, and coated with two layers, the first layer was done by sherardizing process at 400oC for variable periods (15, 30, 60, 120, 240)min, the second layer was applied by polypyrrole (PPY). The results showed that the thickness of sherardizing layer paint is increased when increasing treatment time (15, 30, 60, 120, 240 min). The corrosion performance was evaluated by using polarization method. In addition, it was examined morphological surface of paint layers by using scanning electron microscope (SEM). The results showed that the presence of polypyrrole layer with sherardized coatings, showned significantly increase in corrosion resistance, and coating of low carbon steel by using polypyrrole the conductive polymer with sherardizing process, drastically reduced from the corrosion current density values, as well as the corrosion rate of low carbon steel. The corrosion rate of the the polymer conductive coatings (PPY) on low carbon steel without sherardizing coating (as received) is 19.5 mpy while incorporation of PPY and sherardizing gives corrosion rate of 0.00371 mpy.

Insight into the anti-corrosion performance of electrodeposited silane/nano-CeO2 film on carbon steel

A thin film of bis-amino silane of bis-[triethoxysilylpropyl]amine (BTSPA) was coated on carbon steel surface by electrodeposition and then chemically modified by adsorption of CeO2 nanoparticles. The composition and structure of BTSPA/CeO2 composite film were characterized by electron microprobe analysis, X-ray photoelectron spectroscopy and infrared reflection absorption spectroscopy, while the anti-corrosion performance of the composite film on carbon steel was investigated using electrochemical impedance spectroscopy and scanning reference electrode technique. The results demonstrated that the BTSPA/CeO2 composite film formed on the BTSPA film electrodeposited at −0.8V vs. SCE, which exhibited an enhanced corrosion protection for carbon steel and an improvement of adhesion between substrate and outer coating. The CeO2 nanoparticles incorporated/absorbed into the SiOSi network of the BTSPA film were able to promote the condensation of hydrolysis product SiOH groups to the SiOSi network on the surface and to provide a barrier and corrosion inhibition properties for carbon steel, which is beneficial for improvement of the corrosion protection of the composite film for carbon steel.

Polyaniline/polyvinyl chloride blended coatings for the corrosion protection of carbon steel

Abstract This article presents the corrosion protection ability of blended polyaniline (PANI) and polyvinyl chloride (PVC) polymers applied on 1010 steel. The PANI/PVC blends, as well as pure PANI coatings, were fabricated via a casting method and characterized using infrared spectroscopy. Carbon steel substrates protected with the coatings were subjected to 40 day exposure tests in saline (3% NaCl) and acidic (0.1 M HCl) environments and subsequently analyzed using electrochemical methods Electron microscopy (SEM) and spectroscopic methods (EDS and XPS) were used to study the corroded surface of the 1010 steel underlying the protective coating, as well as the polymer coating itself. The PANI/PVC blends demonstrated superior corrosion protection in both environments as compared to pure PANI and pure PVC coatings. The PANI/PVC blend with a 1/1 proportion offered the most effective corrosion protection in acidic and saline environments based on high charge transfer resistance values and corrosion potential values that approach zero volts. The corrosion protection abilities of the blended coatings are attributed to a combination of barrier protection from the PVC and the formation of a protective oxide layer at the steel-to-polymer interface that is facilitated by the conductivity of PANI.

An investigation on the effect of H 3 PO 4 and HCl-doped polyaniline nanoparticles on corrosion protection of carbon steel by means of scanning kelvin probe

In this work, the effect of H3PO4 and HCl dopants on the corrosion protection properties of polyaniline nanoparticles (PANs) dispersed in epoxy novolac, coated on carbon steel was compared using the Scanning Kelvin Probe (SKP). The nanometeric size and uniform dispersion of PANs in the coating were confirmed by scanning and transmission electron microscopy. Conductivity test, Potentiodynamic measurements and SKP technique were used to study theeffect of dopant type on the corrosion behavior of carbon steel in presence of PANs. The results show that PANs-containing nanocomposites can stabilize the potential of steel substrate in a passive state. Furthermore, variation coefficient (VC) of the surface Volta potential differences was introduced as an index for detection of the corrosion uniformity under the coating in presence of PANs. According to SKP results, the protection ability of coatings was improved in presence of PANs. In addition, the steel corrosion under the coating containing HCl-doped PANs tended to be more localized than that under the coating containing H3PO4-doped PANs. This is attributed to aggressive and inhibitive roles of chloride and phosphate anions respectively.

Hierarchically structured carbon nanotube–polyaniline nanobrushes for corrosion protection over a wide pH range

Carbon nanotube–polyaniline nanobrushes with a hierarchical core–shell structure offer superior corrosion protection for carbon steel over the full pH-range.

Heating-Induced Enhancement of Corrosion Protection of Carbon Steel by a Nanocomposite Film Containing Mussel Adhesive Protein

Application of protective coatings on metals may involve a thermal treatment process. In this study, the effect of thermal treatment up to 200°C on the corrosion protection was investigated for nanocomposite films composed of mussel adhesive protein (MAP), CeO2 nanoparticles and Na2HPO4 deposited on carbon steel. The morphology and microstructure of the pre-formed nanocomposite film were characterized by scanning electron microscopy/energy dispersive spectroscopy and atomic force microscopy (AFM). The changes in the chemical structure of the nanocomposite film due to the thermal treatment were investigated by infrared reflection absorption spectroscopy. The corrosion protection of the unheated and heated nanocomposite films on carbon steel was evaluated by electrochemical impedance spectroscopy and details of the corrosion process were elucidated by in-situ AFM measurements in 0.1 M NaCl solution. The results show a certain increase in the corrosion protection with time of the nanocomposite film for carbon steel. The analyses reveal that thermal treatment leads to a reduction of water molecules in the nanocomposite film, and an enhanced cross-linking and cohesion of the film due to oxidation of catechols to o-quinones. As a result, the film becomes more compact and gives improved corrosion protection for carbon steel.

Effect of Nanoparticles on Wettability of Nanocoating on Carbon Steel

Nanocoatings plays an important role in coating industry. The solution was being prepared through copolymerization of epoxy resin hardener and with the incorporation of metal oxide nanoparticles, Zinc Oxide (ZnO) and Silica (SiO2). ZnO and SiO2 were synthesized using sol-gel. Epoxy hardener acted as host while the metal oxide nanoparticles as guest components. The formulation of nanocoatings with excellent adhesion strength and corrosion protection of carbon steel was studied. The performance of wetting ability with different medium was analysed using contact angle. Water medium showed the addition of 3wt% of hybrid between ZnO and SiO2 was the best nanocoating to form hydrophobic surface and was also the best nanocoating surface to form hydrophilic surface with vacuum oil dropping. In oil dropping, the contact angle was smaller than 90° and the water drop tends to spreads on surface.

Adsorption and performance of the 2-mercaptobenzimidazole as a carbon steel corrosion inhibitor in EDTA solutions

This study presents a thermodynamic analysis of the adsorption and anti-corrosion performance of 2-mercaptobenzimidazole (2-MBI) on carbon steel in EDTA-Na2 solutions. The adsorption of the inhibitor on the metal surface was studied as a function of the concentration of the inhibiting species and the temperature of the system. The corrosion inhibition efficiency was studied by electrochemical impedance spectroscopy and mass loss tests. The results show that the adsorption of the inhibitor onto the metal surface behaves according to the Langmuir model, following an endothermic process. The inhibitor is chemically adsorbed onto the carbon steel surface. The efficiency of corrosion inhibition was above 93%, which was confirmed by both mass loss tests and the electrochemical impedance technique. The good performance of the corrosion inhibitor was maintained up to 24 h after the inhibitor was added to the corrosive EDTA-Na2 solutions. When the ratio of the volume of solution/exposed area was reduced, a decrease in the area covered by the inhibitor was observed. The best cost/benefit ratio for the corrosion protection of carbon steel was obtained when the number of moles of the inhibitor per surface area was maintained at 2.68 mmol cm−2.

Corrosion protection of carbon steel by solvent free epoxy coating containing hydrotalcites intercalated with different organic corrosion inhibitors

Abstract Hydrotalcites intercalated with two different corrosion inhibitors: 2-benzothiazolythio-succinic acid (BTSA) and benzoate (BZ) were prepared by coprecipitation method and incorporated (1.5 wt.%) in solvent free epoxy coatings. The obtained hydrotalcites were characterized using infrared spectroscopy, X-ray diffraction, scanning electron microscopy and zeta potential measurements. The solid suspensions in epoxy resin were characterized by rheology and Turbiscan. The corrosion protection performance of the epoxy coating containing hydrotalcites applied on carbon steel was evaluated by electrochemical impedance spectroscopy, salt spray test and adhesion measurement. It was shown that the BTSA and BZ were intercalated in hydrotalcite and their loading was about 22 wt.% and 27 wt.%, respectively. The presence of BZ modified hydrotalcite (HT-BZ) improved significantly the corrosion protection of solvent free epoxy coating. Corrosion protection performance of epoxy coating containing HT-BZ was higher than that of epoxy coating containing BTSA modified hydrotalcite (HT-BTSA). The corrosion protection performance of coatings appears to depend on the dispersion degree of hydrotalcite particles in the epoxy matrix and the solubility of organic inhibitor in the electrolyte.

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

In this work the complexation of the guest molecule (dibenzylthiourea-DBT) with α and β forms of hydroxypropylated cyclodextrins was evaluated in solution and in the solid state by different techniques. It was shown that the inclusion complexes were obtained and the aromatic moieties of DBT are points of interaction in the structure of the guest. The inhibitory action of these inclusion compounds in carbon steel corrosion in acidic medium was evaluated by polarization curves, electrochemical impedance diagrams and weight loss measurements. There is an enhancement of the inhibitory action against the carbon steel corrosion in HCl solution when the DBT was encapsulated in inclusion compounds whereas the alone hydroxypropylated cyclodextrins did not present an inhibitory effect. It was concluded that these inclusion compounds could be a good alternative to introduce molecules with low solubility in aqueous media and still increase their inhibitory action.