Employment of in silico in prediction of furan derivatives as efficient corrosion inhibitors for mild steel in acidic media

The effect of extract of Azadirachta excelsa leaves as corrosion inhibitor on mild steel in hydrochloric acid medium was investigated using weight loss method. By using data obtained, the corrosion rate (CR), inhibition efficiency (IE) and surface coverage was calculated. Extracts of Azadirachta excelsa leaves in different concentration were used as natural inhibitor. The inhibition efficiency of mild steel in 1 M hydrochloric acid increased as the increasing of concentration of plant extract. The surface morphological changes are recorded using the FESEM analysis. The entire study proves that Azadirachta excelsa leaves extract was non-toxic, cost effective corrosion inhibitor for mild steel in acid medium.

The inhibition performance of some furan derivatives, namely, methyl 2-furoate, ethyl 2-furoate, and amyl 2-furoate on mild steel in normal hydrochloric acid medium ( HCl) at , was studied by weight loss, potentiodynamic polarization, electrochemical impedance spectroscopy (EIS), and electrochemical frequency modulation measurements (EFM). Furan derivatives inhibit the acidic corrosion even at very low concentrations, reaching a value of inhibition efficiency up to 93% at a concentration of . The results obtained from the different corrosion evaluation techniques are in good agreement. Polarization curves indicate that the studied furan derivatives are mixed-type inhibitors. Data obtained from EIS measurements were analyzed to model the corrosion inhibition process through an appropriate equivalent circuit model. A constant phase element has been used. The adsorption of furan derivatives on the steel surface in HCl solution was found to obey Langmuir’s adsorption isotherm with a negative value of the free energy of adsorption . Molecular dynamics simulations were carried out to establish the inhibition mechanism.

The corrosion inhibition effect of acid extract of the pericarp of the fruit Garcinia mangostana on mild steel in hydrochloric acid medium is studied.Using weight-loss data, corrosion rate (CR) and thermodynamic parameters such as energy of activation for corrosion of mild steel (E), heat of adsorption of the inhibitors on the metal surface (Q) and change in free energy (∆G) are calculated.Adsorption isotherm is also recorded between log C and θ.Electrochemical parameters are evaluated from AC impedance and Tafel polarization studies in the presence and absence of different concentrations of inhibitor.Infra-red spectra are recorded for the extract and the adsorption product to find out the changes in the functional group frequencies of the organic components of the extract.The surface morphological changes are analysed using the SEM images.The entire study shows that the pericarp extract of the fruit G. mangostana is a non-toxic, cost-effective corrosion inhibitor for mild steel in acid medium.

The adsorption and corrosion inhibition effect of acid extract of the seeds of Areca catechu on mild steel in hydrochloric acid medium were analyzed. Inhibition efficiency and thermodynamic parameters such as energy of activation for corrosion reaction of mild steel (E), heat of adsorption of the inhibitor on the metal surface (Q), change in entropy (∆S), and change in free energy (∆G) were obtained using weight-loss data. The nature of adsorption of the inhibitor on the metal surface was verified by plotting Temkin’s adsorption isotherm. Electrochemical parameters were obtained by AC impedance and Tafel polarization studies. Infrared (IR) spectra and scanning electron microscope techniques were also employed to examine the mechanism of corrosion inhibition property. All the results obtained were encouraging and hence bring to light a new alternate, eco-friendly material for the corrosion inhibition of mild steel in acid medium.

This paper deals with a review of the inhibition activity of various reported Schiff bases on the deterioration of mild steel in hydrochloric acid and sulfuric acid media. Mild steels find wide applications in structural, automobile and petrochemical industry, where acid solutions such as hydrochloric acid, sulfuric acid are commonly being used as pickling or descaling agents. The undue deterioration of metal during pickling can be controlled by adding a suitable inhibitor to the pickling solution. Schiff bases are widely being employed in such applications. This paper highlights the influence of structure–inhibition activity relationship of Schiff base compounds on their performance as corrosion inhibitors of mild steel in acid media. The information provided finds a useful practical application for different industrial fields in the selection of best-performing inhibitors and also for the researchers involved in the development of new novel corrosion inhibitors for mild steel in acid media.

Acetophenone derivatives are eco-friendly corrosion inhibitors to prevent corrosion of mild steel (MS) in acidic medium. In this work, the inhibition effect of 3-nitroacetophenone (3-NA) on the corrosion of MS in acidic medium (1 N HCl) was investigated using weight loss measurements, electrochemical measurements, scanning electron microscopy, energy-dispersive X-ray spectroscopy, and quantum chemistry analysis. The studies were performed using different concentrations of inhibitors and at different temperatures. The results indicated that the inhibition efficiency of 3-NA increases with an increase in inhibitor concentration and reaches to a maximum of 64% at inhibitor concentration of 250 ppm at 30°C. The potentiodynamic polarization measurement indicated that 3-NA acts as mixed category of interdict. The adsorption of 3-NA on MS surface followed the Langmuir adsorption isotherm. The mode of adsorption of 3-NA on MS surface was further studied by quantum chemical calculations based on density functional theory (DFT). The results plainly revealed that 3-NA performs fairly as corrosion interdict for MS in acidic medium.

Experimental and computational studies of Nicotiana tabacum leaves extract as green corrosion inhibitor for mild steel in acidic medium

The corrosion behavior of aluminum and mild steel in hydrochloric acid medium was studied using a nicotinic acid hydrazide as inhibitor by potentiodynamic polarization, electrochemical impedance spectroscopy technique and gravimetric methods. The effects of inhibitor concentration and temperature were investigated. The experimental results suggested, nico- tinic acid hydrazide is a good corrosion inhibitor for both aluminum and mild steel in hydrochloric acid medium and the inhi- bition efficiency increased with increase in the inhibitor concentration. The polarization studies revealed that nicotinic acid hydrazide exhibits mixed type of inhibition. The inhibition was assumed to occur via adsorption of the inhibitor molecules on the aluminum and mild steel surface and inhibits corrosion by blocking the reaction sites on the surface of aluminum.

A recent study has shown that Schiff base OHMHI is an effective inhibitor of the corrosion of mild steel in acidic media. The study utilized weight loss measurements and electrochemical techniques, such as EIS and potentiodynamic polarization, to analyze the corrosion inhibition efficiency of OHMHI. The results of the study show that the presence of OHMHI in the corrosive environment significantly reduced the corrosion rate of mild steel and increased its corrosion resistance. The impedance spectra analysis indicated that OHMHI was adsorbed on the surface of mild steel, providing a protective layer. The potentiodynamic polarization study confirmed the protective role of OHMHI by showing an increase in the passive current density of the mild steel in the presence of OHMHI. The inhibitory efficiency of OHMHI was found to be 96.1%, indicating that it is an effective corrosion inhibitor for mild steel. The study also investigated the optimal conditions for the use of OHMHI as a corrosion inhibitor, with a concentration of 0.5 mM and a temperature of 303 K being chosen. The Langmuir adsorption isotherm concept was used to demonstrate the physical and chemical adsorption of OHMHI on the surface of mild steel. Morphological investigations of the uninhibited and inhibited surfaces of the mild steel specimen were examined using scanning electron microscopy (SEM) analysis. Furthermore, computational investigations using density functional theory (DFT) and experimental data were merged to explore the corrosion inhibition efficiency and mechanism of inhibition. Although the results are promising, further studies are needed to determine the long-term effects of OHMHI on mild steel corrosion and to evaluate its effectiveness under different environmental conditions. Overall, the study highlights the potential of OHMHI as an effective corrosion inhibitor for mild steel in acidic media.

The water soluble composite poly(vinylpyrrolidone–methylaniline): A new class of corrosion inhibitors of mild steel in hydrochloric acid media

The inhibitive action of an examined expired Ambroxol drug on the corrosion of mild steel in 1 M HCl and 1 M H2SO4 acid medium has been studied by weight loss and electrochemical techniques. The weight loss techniques result was discussed. The inhibition efficiency increases with increasing the concentration of the inhibitor. Electrochemical studies data support that examined expired drug is an efficient inhibitor for mild steel corrosion. The adsorption of the examined drug obeys Langmuir’s adsorption isotherm. Polarization studies indicate that this inhibitor acts as a mixed type inhibition. The various thermodynamic parameters were calculated and discussed. The protective film formed on the surface was confirmed by SEM. The data collected from the studied techniques are in good agreement to confirm the ability of using expired Ambroxol drug as corrosion inhibitor for mild steel in both acid media.

The corrosion behaviour of mild steel in 0.5 M H2SO4 solution containing various concentrations of a p-toluene sulphonic acid doped copolymer formed between aniline and o-toluidine was investigated using weight loss, polarization and electrochemical impedance techniques. The copolymer acted as an effective corrosion inhibitor for mild steel in sulphuric acid medium. The inhibition efficiency has been found to increase with increase in inhibitor concentration, solution temperature and immersion time. Various parameters like Ea for corrosion of mild steel in presence of different concentrations of inhibitor and ΔGads, ΔH0, ΔS0 for adsorption of the inhibitor, revealed a strong interaction between inhibitor and mild steel surface. The adsorption of this inhibitor on the mild steel surface obeyed the Langmuir adsorption equation.

2[2‐Oxo‐phenyl hydrazinyl ether] benzamide (2BA) was synthesized, characterized and tested effective for corrosion inhibition of mild steel in 1 N H2SO4 solution using galvanodynamic polarization and electrochemical impedance spectroscopy (EIS) techniques. Polarization resistances calculated from the EIS measurements are in good agreement with those obtained from alternating current (AC) polarization measurements. The mild steel samples were also analyzed by Scanning Electron Microscopy (SEM). The result showed that 2BA is an excellent inhibitor for mild steel in acid medium. The inhibition was assumed to occur via adsorption of the inhibitor molecule on the metal surface. In the 303‐323K temperature range, the 2BA adsorption follows Langmuir isotherm model. The protection efficiency increases with increasing the inhibitor concentration in the range of 250‐1000 ppm but slightly decreases with increasing temperature.

Experimental and theoretical studies on some selected ionic liquids with different cations/anions as corrosion inhibitors for mild steel in acidic 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.