Enhancement of corrosion resistance of the cooling systems in desalination plants by green inhibitor

Advantages of CoS2 nano-particles on the corrosion resistance and adhesiveness of epoxy coatings

Researchers face significant challenges because of the inadequate corrosion resistance and weak adherence of epoxy (EP) coatings. We deal with these issues here by means of a novel nano-composite coating (EP/nano-CoS2). In order to create a composite coating (EP/nano-CoS2), CoS2 nanoparticles (nano-CoS2) were prepared and incorporated to an epoxy (EP) resin. The synthesized CoS2 was characterized using XRD and FT-IR spectroscopic techniques. The mean particle size was determined using Scherer equation and found to be 19.38 nm. The zeta potential was also determined (- 9.78 mV). Electrochemical impedance spectroscopies (EIS) as well as pull-off assessments were used to quantify the EP/nano-CoS2 coating's anti-corrosion capabilities and adhesive power. The findings demonstrate that the EIS variables of the EP/nano-CoS2 composite coating are markedly improved when compared to raw EP coating. The corrosion resistance or even adhesion of EP protective layer can be markedly increased by using the synthesized nanoparticles as nano-fillers.

Thermodynamic, chemical, and electrochemical studies of Aloe ferox Mill extract as a naturally developing copper corrosion inhibitor in HCl solution

Copper can be susceptible to corrosion in acidic cleaning solutions for desalination system, especially if the solution is highly concentrated or if the cleaning process involves extended exposure to the acid. In the current work, Aloe ferox Mill (AFM extract) can be used as a natural origin corrosion inhibitor for copper in 1.0 M HCl solution. The corrosion mitigation qualities of AFM extract were assessed by means of electrochemical, gravimetric, and surface examinations. AFM extract is a mixed-type inhibitor, based on polarization research findings. The inhibitory effectiveness of AFM extract rises with concentration, reaching its maximum level (93.3%) at 250 mg L-1. The inclusion of AFM extract raises the activation energy for the corrosion reaction from 7.15 kJ mol-1 (blank solution) to 28.6 kJ mol-1 (at 250 mg L-1 AFM extract).

Chemical, electrochemical, and quantum investigation into the use of an organophosphorus derivative to inhibit copper corrosion in acidic environments

In order to protect the copper against corrosion, a novel corrosion inhibitor known as diphenyl ((2-aminoethyl) amino) (4-methoxyphenyl) methyl) phosphonate (DAMP) was developed. Acid solutions of HCl and H2SO4 were the aggressive solutions employed in this study. Analysis using the FT-IR, 1H-NMR, 31P-NMR, 13C-NMR and BET confirmed that the DAMP was successfully synthesized. The anti-corrosion capabilities of DAMP are evaluated using a combination of chemical, electrochemical and quantum studies. The DAMP has been found to be crucial in preventing the corrosion of copper in both HCl and H2SO4 acid. This was obviously implied by the observation that the corrosion rate of copper in acid solutions decreased when DAMP was added. It is significant to note that 180 ppm produced the highest levels of inhibiting efficiency (96.6% for HCl and 95.2% for H2SO4). The tendency of DAMP to adsorb on the surface of copper through its hetero-atoms (O, N, and P) is the main factor for the anti-corrosion capabilities of DAMP. Results from SEM/EDX tests supported this. The actual adsorption takes place via various active centers, physical and chemical mechanisms that are coordinated with the estimated quantum parameters. Additionally, the adsorption of DAMP adheres to the Langmuir isotherm.

Exploration of rice husk ash as a green corrosion inhibitor immersed in NH4Cl 7.5 % solution

The study reports the development of a liquid smoke solution of rice husk ash (RHA) as a green corrosion inhibitor in NH4Cl solution in approaching corrosion protection for refinery facilities. The recent utilization of RHA has a partial solution to address the possible chemical to form a filming layer to disconnect bare metal and their environment. This work prepared the RHA solution by condensing the RHA vapor before adding it to various concentrations. The corrosion test of potentiodynamic and electrochemicals intends to discover the inhibitor's corrosion resistance before examining the electronic transition corresponding to the contribution of several functional groups using Ultraviolet Visible (UV-Vis) and Fourier-Transform Infrared Spectroscopy (FTIR). Surface evaluation intends to unveil the nature of the corrosion by utilizing the Scanning Electronic and Atomic Force Microscope. The corrosion test result shows the depression of corrosion rate to 0.120 mmpy with high efficiency beyond 96 % in the addition of 7.5 ppm RHA inhibitor. The greater Nyquist semicircle diameter at high concentrations increases the adsorption of the RHA on the surface of C1018. The electronic transition of n-π* and π -π* shows an extensive contribution of C[bond, double bond]C, C[bond, double bond]O, and -OH based on the UV-Vis and FTIR test. The formation of a complex compound of Fe-(NH4Cl-RHA)n blocks the corrosion active sites to reduce the corrosion. This study paves the way for using RHA as an organic compound under NH4Cl conditions, such as in a refinery process facility.

Synthesis, surface activity, and corrosion inhibition capabilities of new non-ionic gemini surfactants

Several environmentally acceptable non-ionic gemini surfactants are synthesized in this work using natural sources, including polyethenoxy di-dodecanoate (GSC12), polyethenoxy di-hexadecanoate (GSC16), and polyethenoxy di-octadecenoate (GSC18). The produced surfactants are confirmed by spectrum studies using FT-IR, 1HNMR, and 13CNMR. It explored and examined how the length of the hydrocarbon chain affected essential properties like foaming and emulsifying abilities. Surface tension examinations are used to assess the surface activity of the examined gemini surfactants. The lower value of critical micelle concentrations (0.381 × 10-4M) is detected for GSC18. Their spontaneous character is shown by the negative values of the free energy of adsorption (ΔGads) and micellization (ΔGmic) which arranged in the order GSC18 > GSC16 > GSC12. Based on theoretical, weight loss, and electrochemical investigations, these novel surfactants were investigated for their possible use in inhibiting carbon steel from corroding in 1 M HCl. Measuring results show that GSC18 inhibits corrosion in carbon steel by 95.4%. The isotherm of adsorption evaluated for the investigated inhibitors and their behavior obeys Langmuir isotherm.

Impact of Co3O4 nanoparticles on epoxy's mechanical and corrosion-resistance properties for carbon steel in seawater

Co3O4 nanoparticles (Co3O4-NPs) are synthesized using the facile solvothermal method. FT-IR and XRD spectroscopic analyses verify the creation of cobalt oxide nanoparticles with an average size of 13.20 nm. Furthermore, Zeta potential assessments were carried out to identify the electrical charge of the surface of the produced Co3O4-NPs, which was found to be -20.5 mV.  In addition, the average pore size of Co3O4-NPs is 19.8 nm, and their BET surface area is 92.4 m/g. The study also concerned the effect of Co3O4-NPs on epoxy's improvement of mechanical and corrosion protection for carbon steel in salt solution. By including Co3O4-NPs in an epoxy (EP) coating, corrosion is effectively prevented by non-permeable protective coatings that effectively reduce the transfer of corrosion ions and oxygen.

Green Synthesis of a Novel Cationic Surfactant Based on an Azo Schiff Compound for Use as a Carbon Steel Anticorrosion Agent

The new cationic surfactant-based azo Schiff compound (azoS8) was prepared, characterized, and investigated as a corrosion inhibitor for carbon steel in 1 M HCl by means of electrochemical approaches in this study. The chemical structure of azoS8 has been verified by the FTIR and 1H NMR spectra. According to the electrochemical system, the examined surfactant is a mixed-type inhibitor. The surfactant azoS8 was an adequate corrosion inhibitor, as evidenced by the reduction in corrosion current densities and the rise in coverage of the surface identified with an evolving inhibitor amount. When the surfactant azoS8 had been added, the capacitive cycle loops on the Nyquist plots were broader, and the dimension of these loops expanded with surfactant azoS8 concentration. This implies that the amount of surfactant azoS8 led to an improvement in the impedance of the steel electrode. The surfactant azoS8 adsorption system is well suited to the Langmuir adsorption isotherm. It was discovered that azoS8 had a Gibbs free energy change value of -27.72 kJ mol-1, which is a mixed adsorption mechanism containing both physisorption and chemisorption.

Novel highly efficient ternary ZnO wrapped PPy-NTs/g-C3N4 nanocomposite as an epoxy coating for corrosion protection

The main goal of this study is to develop an epoxy coating coupled with an organic-inorganic hybrid nanocomposite that can be used as a corrosion-inhibiting pigment on carbon steel. Herein, polypyrrole nanotubes (PPy-NTs), polypyrrole nanotubes/g-C3N4 (PPy-NTs/g-C3N4) and novel nano-composite polypyrrole nanotubes/g-C3N4/ZnO (PGZ) were prepared by facile wet impregnation approach. The developed pigments were investigated using XRD, FTIR, FE-SEM equipped EDS. Electrochemical impedance spectroscopy (EIS) and polarization measurements were used to assess the behavior of the prepared pigments on the anticorrosion performance of epoxy resin coatings. EIS experiments revealed that introducing nano-pigments to neat coatings enhanced the epoxy resin and charge transfer resistance. The anticorrosion performance of the three nano-pigments was assessed as follows: PGZ ˃ PPy-NTs/g-C3N4˃ PPy-NTs.

Synthesis, description, and application of novel corrosion inhibitors for CS AISI1095 in 1.0 M HCl based on benzoquinoline derivatives

This study aims to synthesize and evaluate the corrosion inhibition properties of three newly prepared organic compounds based on benzo[h]quinoline hydrazone derivatives. The compounds structure were characterised using FTIR, 1H-NMR, 13C-NMR and Mass spectroscopy. Electrochemical methods, including Potentiodynamic Polarization (PP), Electrochemical Frequency Modulation (EFM), and Electrochemical Impedance Spectroscopy (EIS) were employed to evaluate the compounds as corrosion inhibitors in HCl (1.0 M) for carbon steel (CS). Additionally, surface examination techniques such as scanning electron microscopy (SEM) and energy-dispersive X-ray spectroscopy (EDX) were used to investigate the surface morphology and elemental composition of the CS before and after exposure to the synthesized compounds. The electrochemical measurements showed that compound VII achieved corrosion inhibition efficiency. SEM and EDX analysis further confirmed the creation of a passive film on the CS surface. These findings demonstrated the potential of benzo[h]quinoline hydrazone derivatives as effective organic corrosion inhibitors for CS in aggressive solution.

Coke Quenching Plenum Equipment Corrosion and Its Dependents on the Quality of the Biochemically Treated Water of the Coke-Chemical Production

Steel corrosion processes that occur due to the effects of the biochemically treated water in coke quenching plenums have been studied. Model investigations into the processes of the corrosion failure of carbon St. 3 steel and alloyed 18Х1MF steel were carried out to study the behavior of the metal exposed to the action of the primary but treated water used for the coke quenching after the metal is heated to 373 K and 773 K. Different types of the corrosion that results from the contact of the carbon steel and alloy steel with the sodium hydroxide biochemically treated water of the coke-chemical production have been described. It was shown that the corrosion failure of the steels results from the formation of the films of hydrated iron oxides that appear in all the test media and these films show different behavior of adhesion to specimen surfaces. It was proved that the water treatment results in a certain decrease of the values of the mass and in-depth corrosion factors for St.3 and 12X1MF steels, however it fails to produce an essential effect when the steel is in constant touch with hot water.

Traditional Chinese medicine extracts as novel corrosion inhibitors for AZ91 magnesium alloy in saline environment

Zingiber officinale Roscoe extract, Raphanus sativus L. extract, Rheum palmatum extract, Coptis chinensis extract, Glycyrrhiza uralensis extract (GUE), Potentilla discolor extract (PDE) and Taraxacum officinale extract (TOE) were screened for the green corrosion inhibitors of AZ91 alloy in saline environment. The experiment results demonstrated that GUE, PDE and TOE can significantly enhance the corrosion resistance of AZ91 alloy by 73.4, 87.6 and 84.6%, respectively. Surface characterization using FTIR, UV–Vis and XPS revealed that the organic compounds of GUE, PDE and TOE can interact with the alloy surface to form a protective physisorbed film, effectively mitigating the corrosion process of AZ91 alloy. The present results may be helpful to discover the new green inhibitors with high inhibition efficiency for AZ91 alloy.

Corrosion mitigation in desalination plants by ammonium-based ionic liquid

CuNi (90:10) alloy is widely used in desalination plants. CuNi alloy corrosion in sulfide-containing seawater is the fundamental problem in the desalination industry. Here we have confronted this difficulty by using ammonium-based ionic liquid (Diethyl (2-methoxyethyl)-methyl ammonium Bis(fluorosulfonyl)imide) [DEMEMA][FSI]. The results revealed that the [DEMEMA][FSI] can suppress Cu–Ni alloy corrosion in a solution of (3.5% NaCl + 10 ppm sulphide) with an efficiency of 98.4% at 120 ppm. This has been estimated by electrochemistry and gravimetry. Furthermore, [DEMEMA][FSI] inhibits the growth of sulfate-reducing bacteria SRB in saline water. Surface morphology testing confirmed [DEMEMA][FSI] adsorption on Cu–Ni surface alloys. In addition, quantum calculations have been used to theoretically predict inhibition efficiency [DEMEMA][FSI].

Improving the sustainability of biodiesel by using imidazolium-based ionic liquid

Corrosion of biodiesel-filled fuel tanks has become a major problem in the use of biodiesel as a new green energy source. The ionic liquid 1-Hexyl-3-methylimidazolium bis(trifluoromethanesulfonyl)imide [C₁₀H₁₉N₂]⁺[C₂F₆NO₄S₂]⁻ was used to control corrosion of C-steel in non-edible biodiesel to resolve this problem. The anti-corrosion and antioxidant properties of the [C₁₀H₁₉N₂]⁺[C₂F₆NO₄S₂]⁻ were characterized using weight loss, electrochemical impedance spectroscopy, total acid number measurements beside SEM and EDX analysis. The findings show that [C₁₀H₁₉N₂]⁺[C₂F₆NO₄S₂]⁻ plays an important role in preventing C-steel corrosion in biodiesel with an efficiency close to 99 percent. The adsorption capability and antioxidant properties of [C₁₀H₁₉N₂]⁺[C₂F₆NO₄S₂]⁻ are the major contributors to the ionic liquid's anti-corrosion properties. We anticipate that this work will help to sustainable expand the use of biodiesel as a renewable energy source.

DFT, Monte Carlo and molecular dynamics simulations for the prediction of corrosion inhibition efficiency of novel pyrazolylnucleosides on Cu(111) surface in acidic media

Five novel pyrazolylnucleosides have been evaluated theoretically for their corrosion inhibition efficiency on the Cu(111) surface in acidic media. DFT calculations were carried out to exhibit the intrinsic properties such as lowest unoccupied (ELUMO) and highest occupied (EHOMO) molecular orbital energies, as well as energy gap (∆E), chemical hardness (η), chemical softness (σ), electronegativity (χ), electrophilicity (ω) and nucleophilicity (ε). The theoretical FT-IR spectra were recorded to indicate the presence of the specific bonds in the studied molecules. The surface interactions between the inhibitor molecules and the metal surface were investigated using molecular dynamics simulations and Monte Carlo (MC) simulations. As a result, we have found that the inhibitor pyrazolylnucleosides 5a-e have strong interactions with Cu(111) surface, and therefore have excellent predictive inhibition power against copper corrosion.

Microbial influenced corrosion of processing industry by re-circulating waste water and its control measures - A review

In this review article, illustrating the impact and fundamental stuff of microbially influenced corrosion (MIC) along with mechanism, maintenance of materials, human life, wellbeing and inhibitors for cooling towers. Corrosion is a natural mechanism of oxidation and reduction of metal ions by chemical and electrochemical processes and microorganism accumulation. MIC occurs through the aggregation of microbes which can be secreting the extra polymeric substances (EPS) that oxidation of the metal surface. According to the reviews, in the cooling water system, the corrosion begins in the anode charge because its oxidation reaction quickly takes place on the metal surface than the cathode charge. Annihilate the corrosion process needs certain helper substances such as chemical or green compounds, called inhibitors. Corrosion inhibitors typically adopt the adsorption mechanism due to the presence of organic hetero atoms. Chemical and green inhibitors are used to prevent corrosion processes and since ancient times, vast quantities of chemical inhibitors have been used in industry due to their effectiveness and consistency. But still, the chemical inhibitors are more toxic to humans and the environment. Instead of chemical inhibitors, green inhibitors (natural products like plant leaves, flowers, stem, buds, roots and sea algae) are developed and used in industries. Generally, green inhibitors contain natural compounds, high inhibition efficiency, economic, eco- and human-friendly, and strong potential features against corrosion. Thus, a lot of research is ongoing to discover the green inhibitors in various parts of plants and seaweeds.

Plant Extracts as Green Corrosion Inhibitors for Different Metal Surfaces and Corrosive Media: A Review

Natural extracts have been widely used to protect metal materials from corrosion. The efficiency of these extracts as corrosion inhibitors is commonly evaluated through electrochemical tests, which include techniques such as potentiodynamic polarization, electrochemical impedance spectroscopy, and weight loss measurement. The inhibition efficiency of different extract concentrations is a valuable indicator to obtain a clear outlook to choose an extract for a particular purpose. A complementary vision of the effectiveness of green extracts to inhibit the corrosion of metals is obtained by means of surface characterizations; atomic force microscopy, scanning electron microscopy, and X-ray photoelectron spectroscopy analysis are experimental techniques widely used for this purpose. Moreover, theoretical studies are usually addressed to elucidate the nature of the corrosion inhibitor—metal surface interactions. In addition, calculations have been employed to predict how other organic substances behave on metal surfaces and to provide experimental work with fresh proposals. This work reports a broad overview of the current state of the art research on the study of new extracts as corrosion inhibitors on metal surfaces in corrosive media. Most constituents obtained from plant extracts are adsorbed on the metal, following the Langmuir adsorption model. Electron-rich regions and heteroatoms have been found to be responsible for chemisorption on the metal surface, whereas physisorption is due to the polar regions of the inhibitor molecules. The plant extracts compiled in this work obtained corrosion inhibition efficiencies above 60%, most of them around 80–90%. The effect of concentration, extraction solvent, temperature, and immersion time were studied as well. Additional studies regarding plant extracts as corrosion inhibitors on metals are needed to produce solutions for industrial purposes.