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A novel compound was synthesized by cyclohexylamine, acetophenone and cinnamaldehyde through Mannich reaction in laboratory to use as corrosion inhibitor for steel in acidification process.

The corrosion and inhibition of 13Cr stainless steel in conventional acidification solution were investigated by electrochemical measurements and soaking experiments. The corrosion appearance was observed with scanning electron microscope on the whole surface of 13Cr stainless steel in 20% HCl solution, and the protection film was confirmed on the surface in presence with inhibitor.

Results manifested that the inhibitor C23H27NO can effectively inhibit the corrosion reaction by forming an adsorption layer function as a barrier. Polarization curves indicated that the mixed inhibitor can reduce anodic dissolution and cathodic hydrogen evolution reactions simultaneously. The results of impedance measurements indicated that this inhibitor cannot change the corrosion mechanism of 13Cr stainless steel in 20% HCl solution. The results of the study can provide a theoretical basis for the application of 13Cr stainless steel in conventional acidification solutions during oil well acidification construction process.

A novel compound was synthesized by cyclohexylamine, acetophenone and cinnamaldehyde through Mannich reaction in laboratory to use as corrosion inhibitor for steel in acidification process. The corrosion and anti-corrosion mechanism of 13Cr steel in acid solution was proposed.

This paper aims to introduce a method to reduce corrosion caused by acidic-oxidized polymer degradant through subsection injection with different inhibitor.

This paper introduced a method to reduce corrosion caused by acidic-oxidized polymer degradant through subsection injection with different inhibitor.

The experimental results indicated that the influence of pre-corrosion status on corrosion rate and effectiveness of corrosion inhibitor are significant. The corrosion inhibitors in both injection stage inhibited the corrosion process by preventing the contact of corrosive medium and steel surface through formation of a protective film on the surface of N80 steel. The corrosion rate of polymer degradant can be reduced to 0.63 g/m 2 h through subsection injection with different inhibitor.

This result will increase the production of polymer injection plugging wells through expanding the application of acidic-oxidized polymer degradant.

This concluding part reviews the actions of inhibitors to acidic, ammonical, organic, atmospheric and miscellaneous product corrosion on aluminium. The comprehensive reference list is also concluded.

The purpose of this study is to study corrosion inhibition of Bronze alloy B66 by 4-amino-3-methyl-1,2,4-triazole-5-thione (MTSNH) in 3 per cent NaCl solution. Archaeological bronze artefacts often are stored or displayed in uncontrolled conditions and may suffer from dangerous active corrosion processes that can lead to their destruction. The most dangerous form of archaeological bronze degradation is due to a cyclic reaction that involves copper from the pure alloy and chlorine as a pathogenic agent. A protection treatment can be used to protect them from the corrosion environment and stabilise them to avoid further degradation during exhibition or storage. Starting from its initial assessment as a corrosion inhibitor for pure copper, nowadays benzotriazole (BTA) is in widespread use for the conservation of copper-based artefacts, but unfortunately, BTA is toxic and a suspected carcinogen. The development of new and safe protection systems would offer a choice of alternative products to conservation-restoration professionals for the effective and safe stabilization and protection of metal artefacts. In this investigation, a new organic compound, namely, MTSNH, was synthesized, characterized and tested as a corrosion inhibitor for Bronze B66 (similar to archaeological bronze) in 3 per cent NaCl solution using potentiodynamic polarization studies and electrochemical impedance spectroscopy (EIS) at room temperature. It has been observed from the corrosion rate that the inhibition efficiency increased with increasing concentration of MTSNH. Potentiodynamic polarisation results revealed that the compound acted as a mixed-type inhibitor. Impedance studies indicated that protection occurs through adsorption of the inhibitor on the metal surface, with important modification to the mechanism of corrosion. Surface analysis was carried out using scanning electron microscopy scanning electron microscopy (SEM)/energy dispersive spectrometry (EDX) techniques to verify the electrochemical results.

The inhibition efficiency of MTSNH is investigated by potentiodynamic polarization, EIS and surface analysis.

The synthesized MTSNH act a good inhibitor in 3 per cent NaCl and inhibition efficiency increases with inhibitor concentration. Polarisation curves showed that the inhibitor is mixed. The EIS measurements showed that the inhibitor acted throughout the formation of film at the bronze surface. The surface analysis confirms this result.

The adsorption of the MTSNH on the metal surface can markedly change the corrosion resisting property of metal. Therefore, the study of the relation between adsorption and corrosion inhibiting is of a great importance.

Plant development and use as green corrosion inhibitors are already recognized as one of the most environmentally friendly and effective protocols. In recent years, efforts have been made to find green corrosion inhibitors as an alternative to synthetic inhibitors for metals in acid medium. This paper aims to report the investigation of use of aqueous extracts of Tamarindus Indica as green inhibitors for corrosion of metals within different circumstances.

The use of Tamarindus Indica extracts (leaves, stem, fruit pulp and fruit husk) as corrosion inhibitors for mild steel and aluminum in different mediums (HCl, H2SO4, formic acid and citric acid) at different temperatures was investigated.

The inhibitory efficiency of Tamarindus Indica extracts increases with increasing concentration and decreases with increasing temperature. Langmuir is the adsorption isotherm, and the extract (inhibitor) is a mixed-type inhibitor (physisorption and chemisorption).

Tamarindus extracts (leaves, stem, fruit pulp and fruit husk) are effective inhibitors and can be used to protect metals from corrosion at different circumstances.

To the best of the authors’ knowledge, this is the first review that discusses the use of Tamarindus Indica extracts as corrosion inhibitors for metals.

The purpose of this study is to investigate the corrosion behaviour of X70 steel in the presence and absence of various concentrations of inhibitor N-(2-o-Tolyl azophenyl)-acetamide (NTAA) in a CO₂ environment.

The temperature was set at 80°C, and the flow velocity was 1.5 m/s. The inhibitor concentrations were 10, 20, 30, 60 and 80 ppm, and the CO₂ partial pressure was 0.8 MPa. Weight loss method, pitting depth measurement, scanning electron microscopy and electrochemical techniques were used to investigate the inhibitory effects of the inhibitor NTAA.

The results showed that a small peak emerged in the curve of the corrosion rate versus inhibitor concentration plot at 20-30 ppm. Polarisation studies revealed that the anodic Tafel slopes changed greatly in the presence of an inhibitor; NTAA behaved as an anode-type inhibitor. At concentrations of 20-30 ppm, the incomplete coverage of the metal surface by inhibitor molecules resulted in macroscopic galvanic corrosion.

Corrosion behaviour of X70 steel in the presence and absence of various concentrations of an anode-type inhibitor was assessed. Cathodic Tafel slopes are almost unchanged, while the anodic Tafel slopes change significantly with the increase in inhibitor concentration. The corrosion rates of 20 and 30 ppm are almost three times of that of 10 ppm, which is because of the macroscopic galvanic corrosion caused by the inadequate coverage of inhibitor on steel surface.

The paper aims to report an experimental investigation of the effectiveness of an alkyl amine‐based inhibitor on the corrosion behavior of 1018 carbon steel in sea water. The adsorption equilibrium for this corrosion inhibitor on carbon steel was also investigated. The corrosion inhibitor was evaluated based on parameters such as inhibitor concentration, temperature, stirring speed and pH.

The experimental setup employed an autoclave with a flow circulation system. Weight loss determinations and electrochemical techniques such as polarization resistance and potentiodynamic polarization were used to detect and monitor the performance of the corrosion inhibitor. Surface examination of the steel substrate before and after applying different doses of inhibitor was undertaken using Fourier transform infrared spectroscopy (FT‐IR), scanning electron microscopy (SEM), and energy dispersive spectrometry (EDS).

Inhibition efficiency was enhanced by adsorption of amine‐containing functional groups on the steel surface. This adsorption capacity was measured and fitted Langmuir and Shawabkeh‐Tutunji isotherms and was found to require a maximum requirement of 1.08 mg of corrosion inhibitor to provide a monolayer of cover on the carbon steel surface. The inhibition efficiency increased with increasing the inhibitor concentration and solution pH. Moreover, increasing the solution temperature and stirring speed had an adverse effect on inhibition efficiency. Polarization data fitted by the Butler‐Volmer Equation showed the values of anodic and cathodic Tafel coefficients were an average of 0.8 and 0.2, respectively. The measured corrosion rates decreased rapidly within the first hour after commencing the experiments, which is related to the formation of a protective oxide film.

More inhibitor concentrations can be studied in order to draw more comprehensive conclusions on the efficiency of the tested inhibitor.

The effect of alkyl amine‐based inhibitor on the corrosion inhibition characteristic of 1018 carbon steel (CS) in sea water was determined at different inhibitor concentrations, temperatures, stirring speeds and pH.

The new information reported in this paper is the effect of alkyl amine‐based inhibitor on the corrosion characteristics of 1018 carbon steel in seawater using an autoclave with a flow circulation system. The paper is valuable to researchers in the area of corrosion inhibitors and oil and gas industry.

COPPER is by far the most important non‐ferrous metal used in industry. By virtue of its valuable physical and mechanical properties, long life, comparative cheapness and high scrap value, it occupies a position next only to iron and steel in commercial importance.

This paper aims to evaluate the inhibitive effect and adsorption behavior of 5-(ethylthio)-1H-tetrazole (EHT) and 5-(benzylthio)-1H-tetrazole (BHT) on copper in a sulfur-ethanol system.

Evaluation was carried out using electrochemical measurement and surface analysis techniques. Measurements of static friction coefficient by scanning electron microscopy and contact angle analysis were applied and finally confirmed the existence of the adsorbed film. The inhibitive mechanism of the two compounds was evaluated by means of quantitative calculation and molecular dynamics simulation. The friction coefficient of corrosion surface before and after adding corrosion inhibitor was determined through static friction coefficient measurements.

The electrochemical measurement indicated that the most effective concentration of two corrosion inhibitors was 70 mg L^–1, while the inhibition efficiency of that was EHT > BHT. The friction coefficient data showed that the addition of corrosion inhibitor reduced the roughness of the corrosion surface. Adsorption behavior of two inhibitors followed the Langmuir’s adsorption isotherm and was attributed to mixed-type adsorption. The results of quantitative calculation and molecular dynamics simulation showed that tetrazole rings of the two inhibitors and its connected S atoms were adsorbed on Cu(111) surface in parallel.

The corrosion inhibition performance of two tetrazolium derivatives in a sulfur-ethanol system was studied by combining experiments with theory, which provided a theoretical basis for the future research.

The aim of this paper is to investigate peach juice as a cheap, raw, green and non‐toxic anti‐corrosion material for mild steel corrosion in hydrochloric acid at different temperatures.

The corrosion inhibition of mild steel in 1 M HCl solution in the presence of peach juice at temperature range of 30‐60°C and concentration range of 5‐50 cm³/l was studied using weight loss and polarization techniques. The inhibition effect, adsorption characteristics, mathematical and electrochemical modeling of peach juice were addressed.

Results show that inhibition efficiency rose with the increase of inhibitor concentration and temperature up to 50°C, while at temperatures above 50°C the values of efficiency decreased. The inhibitor adsorbed physically on metal surface and followed the Langmuir adsorption isotherm. Monolayer formed spontaneously on the metal surface. Maximum inhibition efficiency obtained was about 91 percent at 50°C in the 50 cm³/l inhibitor concentration.

This work is an attempt to find a new, safe to environment, non‐toxic corrosion inhibitor. Peach juice is a readily available material in Iraq and Middle East markets.