Eco-friendly Corrosion Inhibitor Research Articles

Eco-friendly corrosion inhibitors: Synergistic effect of ethanol extracts of calotropis for corrosion of mild steel in acid media using mass loss and thermometric technique at different temperatures

The inhibitive action of leaves (LV), Latex (LX) and Fruit (FT) extracts of Calotrpis procera and Calotropis gigantea on mild steel corrosion in HCl, H2SO4 and mixture of solutions have been studied using mass loss and thermometric technique at different temperatures. The results indicate that the ethanolic extracts functioned as a good corrosion inhibitor in both environments and inhibition efficiency increased with extracts concentration. A mechanism of chemical adsorption of the plants components on the surface of the metal is proposed for the inhibition behavior. The inhibition efficiency increases up to 86.37%.

Thymus algeriensis extract as a new eco-friendly corrosion inhibitor for 2024 aluminium alloy in 1 M HCl medium

The inhibitive behaviour on 2024 aluminium alloy of Thymus algeriensis extract was investigated in an aerated 1M HCl solution via weight loss, gasometric and electrochemical impedance spectroscopy (EIS) techniques. It was found that the addition of the extract reduces the corrosion rate of aluminium alloy. The inhibition efficiency increases with increasing extract concentration and attained 78.7% at 0.75g/L. The inhibitive effect of the tested extract was discussed in view of adsorption of its components on the aluminium surface. The adsorption of the extract components of T. algeriensis on the aluminium alloy surface follows Langmuir adsorption isotherm. The effect of the temperature on the corrosion behaviour with addition of the optimal concentration of T. algeriensis extract was studied in the temperature range of 298 and 338K. The inhibition efficiency is independent of temperature. The presence of extract increases the activation energy of the corrosion process of aluminium alloy. The synergistic action caused by iodide ions on the corrosion inhibition of aluminium in 1M HCl by 0.75g/L was studied using weight methods at 298K. The inhibition efficiency synergistically increased on addition of potassium iodide.

Strychnos nuxvomica, Piper longum and Mucuna pruriens seed extracts as eco-friendly corrosion inhibitors for copper in nitric acid

The inhibitive effect of theStrychnos nuxvomica(SN),Piper longum(PL) andMucuna pruriens(MP) seeds extract on the corrosion of copper in 3 M HNO3solution was studied using gravimetric and electrochemical techniques.

A Study of <i>Eruca vesicaria</i>, <i>Bromelia hemisphaerica</i> and <i>Erythrina americana</i> as Green Corrosion Inhibitors for Carbon Steel in Sulfuric Acid

A study of Eruca vesicaria, Bromelia hemisphaerica and Erythrina americana as eco-friendly corrosion inhibitors for 1018 carbon steel in 0.5 M H2SO4 has been carried out by using weight loss tests, potentiodynamic polarization curves and electrochemical impedance spectroscopy measuremnts. Results have shown that the three extracts performed as good corrosion inhibitors, but the Eruca vesicaria exhibited the best performance followed by Erythrina americana. The three inhibitors formed a protective, passive film which protected the steel from corrosion. This was because they contain antioxidants present in their molecular structure with heteroatoms such as N, C and O like phenols, amino acids, etc., which react with metal and environment to form the protective film.

Thermodynamic and Kinetic Parameters of Methanolic Extract of Leaves of Cochlospermum Tinctorium as Eco-friendly Inhibitor for Corrosion of Mild Steel in HCL Medium

Thermodynamic, kinetic and adsorptive parameters of methanolic extract of leaves of Cochlospermum tinctorium as eco-friendly inhibitor for the corrosion of mild steel in HCl medium were evaluated through the weight loss method at 303 K and 311 K. The inhibition efficiency, %IE, increased with increase in extract concentration, but found to be better at 303 K than 311 K. The decrease in %IE with increase in temperature with the average value of 81.88 kJ/mol for activation energy, E a , and the values of free energy, ÄG, for the adsorption process are all supportive of physical adsorption mechanism. The values of heat of adsorption, Q ads,, are all negative, an indication that the adsorption process was exothermal. The half-life, t 1/2 , value increased with increase in inhibitor concentration and low at high higher, implying the inhibitor performance increased with increase in the extract concentration and decreased with rise in temperature. The data best fitted the Langmuir adsorption isotherm.

Amino acid compounds as eco-friendly corrosion inhibitor for N80 steel in HCl solution: Electrochemical and theoretical approaches

Amino acid compounds, namely, 1-(1H-benzo[d]imidazole-2-yl)-N-((furan-2-yl)methylene)methanamine (BIFM) and 1-(1H-benzo[d]imidazole-2-yl)-N-((furan-2-yl)methylene)-2-phenylethanamine (BIFP) were synthesized and studied as inhibitors for N80 steel corrosion in 15% HCl solution using potentiodynamic polarization and electrochemical impedance spectroscopy (EIS) techniques. Polarization studies showed that both studied inhibitors were of mixed type in nature. The adsorption of inhibitors on the N80 steel surface obeys Langmuir adsorption isotherm. The potential of zero charge (EPZC) for the N80 steel was determined by electrochemical impedance spectroscopy method. Scanning electron microscopy (SEM) and Atomic Force Microscopy (AFM) were used to characterize the surface morphology of uninhibited and inhibited N80 steel specimens. The Density Functional Theory (DFT) was employed for theoretical calculations.

Electrochemical behaviour of acetyl G as corrosion inhibitor for mild steel in acid medium

Purpose – The purpose of this paper is to develop an eco-friendly corrosion inhibitor for mild steel in 1 M HCl. Design/methodology/approach – A pharmaceutical drug acetyl G was investigated for its corrosion inhibition efficiency using weight loss method, potentiodynamic polarisation and electrochemical impedance spectroscopy. Findings – The inhibition efficiency increased with increase in inhibitor concentration. Results from polarisation studies revealed mixed type of inhibition. Impedance studies, scanning electron microscopy and Fourier transform spectroscopy confirm the adsorption of inhibitor on the mild steel surface. Research limitations/implications – The drug acetyl G has sulphur and nitrogen atoms which effectively block the corrosion of mild steel and is non-toxic and has good inhibition efficiency. Practical implications – This method provides an excellent, non-toxic and cost-effective material as a corrosion inhibitor for mild steel in acid medium. Originality/value – Application of this drug as a corrosion inhibitor has not been reported yet in the literature. Replacing the organic inhibitors, this green inhibitor shows excellent inhibition efficiency. This is adsorbed excellently on the mild steel surface due to the presence of long chain and hetero atoms. Thus, the drug retards the corrosion reaction.

Alkaloids extract of Retama monosperma (L.) Boiss. seeds used as novel eco-friendly inhibitor for carbon steel corrosion in 1 M HCl solution: Electrochemical and surface studies

Current research efforts now focus on the development of non-toxic, inexpensive and environmentally friendly corrosion inhibitors as alternatives to different organic and non-organic compounds. In this field, alkaloids extract of Retama monosperma (L.) Boiss. seeds (AERS) was tested for the first time as corrosion inhibitor for carbon steel in 1M HCl medium using electrochemical and surface characterization techniques. The obtained results showed that this plant extract's acts as an efficient corrosion inhibitor for carbon steel in 1M HCl and an inhibition efficiency of 94.4% was reached with 400mg/L of AERS at 30°C. Ac impedance experimental data revealed a frequency distribution of the capacitance, simulated as constant phase element. Impedance results demonstrated that the addition of the AERS in the corrosive solution decreases the charge capacitance and simultaneously increases the function of the charge/discharge of the interface, facilitating the formation of an adsorbed layer over the steel surface. Polarization curves indicated that AERS is a mixed inhibitor. Adsorption of such alkaloid extract on the steel surface obeyed to the Langmuir adsorption isotherm. X-ray photoelectron spectroscopy (XPS) showed that the inhibition of steel corrosion in normal hydrochloric solution by AERS is mainly controlled by a physisorption process and the inhibitive layer is composed of an iron oxide/hydroxide mixture where AERS molecules are incorporated.

Quantum chemical and experimental investigations on equipotent effects of (+)R and (−)S enantiomers of racemic amisulpride as eco-friendly corrosion inhibitors for mild steel in acidic solution

The potential of amisulpride drug as a corrosion inhibitor for mild steel in 1M HCl has thoroughly been investigated by electrochemical methods. Polarization curves showed that this compound has high inhibiting properties for steel corrosion in acidic solution and the inhibition efficiency increased with the increase in inhibitor concentration. The adsorption of the inhibitor on the surface of steel has been found to obey a Langmuir adsorption isotherm and the influence of temperature on the adsorption of inhibitors onto a mild steel surface has been reported. Quantum chemical computations at the density functional theory have been applied to study the inhibition performance of (+)R and (−)S enantiomers of racemic amisulpride. The quantitative structure–activity relationship (QSAR) approach has also been used to correlate the quantum chemical parameters with the experimentally determined inhibition efficiencies.

Inhibitory effect of xanthan gum and synergistic surfactant additives for mild steel corrosion in 1 M HCl

Natural polymer xanthan gum (XG) was investigated as eco friendly corrosion inhibitor for mild steel in 1M HCl at 30°C, 40°C, 50°C and 60°C, respectively. The inhibition studies were performed using gravimetric analysis, potentiodynamic polarization, electrochemical impedance spectroscopy (EIS), quantum chemical calculations, scanning electron microscopy (SEM), and UV–visible spectrophotometry. XG significantly reduces the corrosion rates of mild steel. The inhibition efficiency (IE) of the XG increased with increase in concentration, but decreased with temperature; the maximum IE of 74.24% was obtained at concentration of 1000ppm at 30°C. The inhibiting action of XG is synergistically enhanced on addition of very small amount of surfactants sodium dodecyl sulfate (SDS), cetyl pyridinium chloride (CPC) and Triton X-100 (TX). The effect of SDS is more pronounced than other surfactants. Potentiodynamic polarization studies confirm XG as a mixed type inhibitor. Results of weight loss measurements are in good agreement of the results of electrochemical measurements. The UV–visible spectroscopic results indicate the formation of complex between XG and Fe2+ ions during corrosion reaction. Mechanism of inhibition was also investigated by calculating the thermodynamic and activation parameters like ΔG0, Ea, ΔH and ΔS. The adsorption of inhibitor on mild steel surface obeys Langmuir adsorption isotherm. SEM micrographs show a clearly different morphology in presence of XG and XG-surfactant additives and confirmed the existence of an adsorbed protective film on the mild steel surface.

Tragia plukenetii extract as an eco-friendly inhibitor for mild steel corrosion in HCl 1 M acidic medium

A Tragia plukenetii (T. plukenetii) plant extract for use as a low-cost and efficient corrosion inhibitor for mild steel (MS) in 1 M HCl medium has been studied using various methods involving weight loss calculation, electrochemical impedance spectroscopy, and Tafel polarization. The maximum corrosion inhibition efficiency was found to be 88 % at 500 ppm. It was found that the T. plukenetii extract’s inhibition efficiency increased with the inhibitor concentration. The polarization measurement showed that the T. plukenetii plant extract acts as good mixed-type inhibitor. Thermodynamic investigations showed the change in enthalpy, entropy, and free energy. The adsorption mechanism of the extract was investigated using UV–Visible, FT-IR, Raman spectroscopy, and wide-angle X-ray diffraction studies. The inhibitor solution, investigated on the basis of the atomic absorption spectra for MS, revealed decreased dissolution of Fe in the presence of the plant extract. Surface analysis of the metal with and without the plant extract was carried out by using scanning electron microscopy and energy-dispersive X-ray spectroscopy.

Synthesized amino acid compounds as eco-friendly corrosion inhibitors for mild steel in hydrochloric acid solution: electrochemical and quantum studies

Corrosion inhibition performance of synthesized amino acid compounds, namely, (Z)-2-(2-oxoindolin-3-ylideneamino)acetic acid (OYAA) and 2-(2-oxoindolin-3-ylideneamino)-3-phenylpropanoic acid (OYPA) on mild steel in 15-% HCl solution was investigated by means of potentiodynamic polarization and electrochemical impedance spectroscopy (EIS) techniques. Potentiodynamic polarization studies showed that both studied inhibitors were mixed types in nature. The adsorption of inhibitors on the mild steel surface obeyed Langmuir's adsorption isotherm. The potential of zero charge (EPZC) for the mild steel was determined via EIS to discuss the adsorption mechanism. Scanning electron microscopy, energy dispersion X-ray spectroscopy and atomic force microscopy were used to characterize the surface morphology of uninhibited and inhibited mild steel specimens. The density functional theory was employed for theoretical calculations.

Aqueous extracts of olive roots, stems, and leaves as eco-friendly corrosion inhibitor for steel in 1 MHCl medium

This work is devoted to examine the effectiveness of the aqueous extracts of olive (Olea europaea L.) leaves, roots, and stems on corrosion of mild steel in 1 M HCl solution using the weight loss measurement at various temperature and concentration effects. Polarization curves and electrochemical impedance spectroscopy (EIS) methods were employed to evaluate corrosion rate and inhibition efficiency. Corrosion inhibition efficiencies of 89.24, 88.84, and 89.83 % were achieved in 1 M HCl for olive root extract (ORE), olive stem extract (OSE), and olive leaf extract (OLE), respectively. It was found that the different extracts act as a good corrosion inhibitor for the tested system. The inhibitive action of the extract is discussed with a view to the adsorption of its components onto the steel surface which made a barrier to mass and charge transfer. The adsorption of extract components onto the steel surface was found to be a spontaneous process and increases the activation energy of the corrosion process. The inhibition efficiency is greatly reduced as the temperature increased. Experimental results show that corrosion inhibition efficiency increases with concentration of the sample extract. Polarization studies show that olive leaf, root, and stem extracts act as a mixed inhibitor.

Cassava starch graft copolymer as an eco-friendly corrosion inhibitor for steel in H2SO4 solution

Cassava starch graft copolymer (CSGC) was prepared by grafting acryl amide (AA) onto cassava starch (CS). The inhibition effect of CSGC on the corrosion of cold rolled steel (CRS) in 1.0M H2SO4 solution was first studied by weight loss, potentiodynamic polarization curves, electrochemical impedance spectroscopy (EIS) and scanning electron microscope (SEM) methods. The results show that CSGC is a good inhibitor, and inhibition efficiency of CSGC is higher than that of CS or AA. The adsorption of CSGC on steel surface obeys Langmuir adsorption isotherm. CSGC is a mixed-type inhibitor at 20 °C, while mainly a cathodic inhibitor at 50 °C.

Eco-Friendly Corrosion Inhibitor: Experimental Studies on the Corrosion Inhibition Performance of Creatinine for Mild Steel in HCl Complemented with Quantum Chemical Calculations

Eco-Friendly Corrosion Inhibitor: Experimental Studies on the Corrosion Inhibition Performance of Creatinine for Mild Steel in HCl Complemented with Quantum Chemical Calculations

Effect of Acidified Feronia elephantum Leaf Extract on the Corrosion Behavior of Mild Steel

Mild steel is used as a structural material for pipes, tank, reaction vessels, etc. which are known to corrode invariably in contact with various solvents. From the view point of a nation’s economy and financial implications of corrosion hazard, it is necessary to adopt appropriate means and ways to reduce the losses due to corrosion. The use of eco-friendly corrosion inhibitors are increasing day by day. Feronia elephantum leaf extract (FELE) has been tested as eco-friendly corrosion inhibitor for A262 mild steel in 1 M H2SO4 and 1 M HCl solutions using non-electrochemical (Gravimetric, X-ray diffraction analysis, scanning electron microscopy, and Fourier transform infrared spectroscopy) and electrochemical techniques (open circuit potential, potentiostatic polarization, and electrochemical impedance measurements). The protection efficiency is found to increase with increase in FELE concentration but decrease with temperature, which is suggestive of physical adsorption mechanism. The adsorption of FELE on mild steel surface obeys the Langmuir adsorption isotherm. SEM results confirm the formation of a protective layer by FELE over mild steel surface.

Tetraphosphonic acid as eco-friendly corrosion inhibitor on carbon steel in 3 % NaCl aqueous solution

The inhibition activity of a new tetraphosphonic acid (TPA), 2-hydroxy-5-[4-hydroxy-3,5-bis(phosphonomethyl)benzyl]-3-(phosphonomethyl)benzylphosphonic acid, for carbon steel in aerated 3 % NaCl solution, at 1000 rpm, was investigated using open circuit potential (OCP), potentiodynamic polarizations, and electrochemical impedance spectroscopy (EIS) to evaluate the TPA inhibition efficiency. The steel surface was also examined by SEM observations and energy-dispersive X-ray (EDX) analysis. The inhibition efficiency increased with TPA increasing concentration up to 10−3 mol L−1 where the highest inhibition efficiency (88 %) was obtained. The thermodynamic parameters—adsorption equilibrium constant, standard free energy, and activation energy—were calculated to determine the corrosion inhibition mechanism. Results from potentiodynamic polarization and electrochemical impedance spectroscopy revealed the mode of inhibitive action and adsorption of inhibitor molecules. Further, surface morphological examination supports the protective film formation by TPA on carbon steel surface. Inhibitor adsorption was spontaneous (ΔG < 0), supported the physical/chemical adsorption mechanism, and obeyed to the Langmuir adsorption isotherm.

Date palm (Phoenix dactylifera) leaf extract as an eco-friendly corrosion inhibitor for carbon steel in 1M hydrochloric acid solution

Purpose– The purpose of the paper was to investigate the use of aqueous extract of date palm (Phoenix dactylifera) leaf as a green inhibitor for corrosion of carbon steel in 1M hydrochloric acid (HCl) solution.Design/methodology/approach– Extracts from the date palm were used as the main component of an environmentally friendly corrosion inhibitor for use in HCl pickling processes. Inhibition behavior on carbon steel in HCl was investigated using weight loss measurements, linear and potentiodynamic polarization curves, electrochemical impedance spectroscopy and scanning electron microscopy.Findings– The results show that the extract exhibited good inhibition performance in 1M HCl. The inhibition efficiency increased with increase in the concentration of the inhibitor but decreased with increase in temperature. Inhibition efficiency also was found to increase as immersion time increased. The inhibitive action was due to adsorption of the date palm leaf components on the steel, which was consistent with the Langmuir isotherm.Practical implications– Date palm leaf extract (DPLE) is an effective inhibitor at room temperature and can be used to protect plain carbon steel from corrosion in HCl solution.Originality/value– This study provides new information on the inhibiting characteristics of DPLE under specified conditions. The environmentally friendly inhibitor could find possible applications in metal surface anodizing and acid pickling processes.

Synergistic Inhibition Effect of Sodium Tungstate and Hexamethylene Tetramine on Reinforcing Steel Corrosion

Sodium tungstate (Na2WO4) and hexamethylene tetramine (HMTA) are both eco-friendly corrosion inhibitors. In this work, their synergistic corrosion inhibition effects on reinforcing steel in the simulated polluted concrete pore solution containing Cl− were studied by electrochemical techniques including electrochemical impedance spectroscopy and potentiodynamic anodic polarization curve measurements. The morphologies and compositions of the steel surface were characterized by Electron Micro-Probe Analyzer, X-ray photoelectron spectroscopy, and Raman spectroscopy. The results showed that the serious steel corrosion took place in the solution with pH 11.00 and 0.5 M NaCl. However, a stable passive region occurred in the anodic polarization curve of the steel and its corrosion current density decreased dramatically after addition of a mixed inhibitor with 0.01 M Na2WO4 and 0.01 M HMTA to the solution. The inhibition efficiency of the mixed inhibitor reached 97.1%. The surface analyses revealed that a protective composite film was formed on the steel in the solution with the mixed inhibitor, which indicated that the mixed inhibitor had a synergistic inhibition effect on the steel corrosion. Our study also indicated that the mixed inhibitor could effectively control corrosion of the reinforcing steel in cement mortar.

Alginate surfactant derivatives as an ecofriendly corrosion inhibitor for carbon steel in acidic environments

Biopolymer alginate surfactant derivatives were synthesized and their influences as a novel corrosion inhibitor on carbon steel in 1 M HCl were studied using gravimetric, electrochemical, EDX and SEM techniques.